They confiscated my 4 ounce bottle of saline, mostly empty, for my ath-zrh flight.

When I pointed out it was almost empty, they said the container is the problem, that 3.4 oz is the limit. I've never run into a problem with a 4 oz bottle at any airport worldwide. In fact the company markets the 4 oz bottles as approved for carry on.

I have taken ATH-JMK flight and CHQ-ATH flights with nobody saying a peep about the bottle.

Then they make you take out my DSLR and extra lens and iPads too. What ever happened to most airports not requiring iPads to be taken out?

Worst of all, the lounges are outside security so you have to allow time for the hassles of getting through security.

The international liquids limit is 100ml (where a limit exists), and of course the USA is the only country on earth that still uses oz. as a liquid measure. The US TSA converts the 100ml to 3.4oz and this is what appears on their website as the maximum permitted size. So whoever sold you a 4oz bottle has mislead you and you have been lucky to avoid confiscation before now, including when leaving the USA.
The fact that other security checkpoints have failed to spot the size irregularity simply means that nobody has actually looked at the writing on the container before, it would be hard to tell otherwise.
Did you do something to annoy the security staff at ATH, perhaps by loudly complaining that they wanted to scan your Ipad separately, which provoked an extra-close examination as they thought you had something to hide?

If your trip to ZRH was very recent, were you not aware of the "military coup" in next-door Turkey? Wouldn't any sensible country go to a heightened state of alert and intensify security checks until the situation stabilised? Those who travel frequently in Europe are used to the ever-changing requirements at security checkpoints. Part of the idea is that it prevents would-be terrorists from knowing precisely what will be checked on the day they pass through the airport.

Oh, and the lounges. On the extra-Schengen side they have introduced centralised security and the lounges are now after security. The domestic and intra-Schengen side is currently being remodelled, lets see what results.

Only thing I said to them was after they pulled out the bottle.

They said the container is the issue. Well it was mostly empty and there's no way to refill it without a syringe.

Meanwhile they say nothing about my empty 20 oz water bottle.

So is it the size of the container or isn't it?

Now I go on a long flight and have to deal with no way to hydrate my dry eyes.

Again, I've been through dozens of international flights since the liquid limitations. Why the Greeks chose to be sticklers I don't know. I didn't say a peep to them until they grabbed the bottle.

I remember before the Athens Summer Olympics there were security concerns, whether the Greeks would be up to it.

Maybe they decided to be more hardcore about it after that.

It's not an enlightened thing to say but they need to profile, play the percentages and probabilities of ethnic groups, nationalities and religion of people who've been known to try to perpetrate terrorism. That's how law enforcement works, they use probabilities based on historic patterns of behavior.

Reading your OP I thought "here's another victim of the worldwide stupid security measures at airports. Reading your second post, though, I'm almost inclined to say that this served you well. I know you'll get angry at that but let me go point by point:

a) Only thing I said to them was after they pulled out the bottle. The question was not when you said something but what you said and how...

b) Meanwhile they say nothing about my empty 20 oz water bottle. Be glad they didn't spot this very valuable container, you would have had to buy another bottle!

c) So is it the size of the container or isn't it? It's very simple, liquid solutions have to be transported in containers with a capacity of 100 ml. Your saline solution was in a larger container.

d) Now I go on a long flight and have to deal with no way to hydrate my dry eyes. As a medic I can assure you that the security agents (obviously without being aware of that) helped your health: there is no way to keep a few milliliters of a saline solution sterile in a 4 oz. bottle unless you flame the top before and after every use. You risk a good old fashioned conjunctivitis!

e) Why the Greeks chose to be sticklers I don't know. Perhaps it's their genes? Or, come to think of it, perhaps they're just copying the behaviour of their American colleagues from the TSA?

f) I remember before the Athens Summer Olympics there were security concerns, whether the Greeks would be up to it.
Maybe they decided to be more hardcore about it after that. Now why on earth do you un-earth the 2004 Olympics? Yes, there were concerns but not a single nose bled, in contrast to what happened during the Atlanta Olympics.

g) It's not an enlightened thing to say but they need to profile, play the percentages and probabilities of ethnic groups, nationalities and religion of people who've been known to try to perpetrate terrorism. That's how law enforcement works, they use probabilities based on historic patterns of behavior. Have you thought perhaps of the fact that, perhaps, they did do the job the way you describe it and after profiling you they came up with the conclusion that you fit the pattern of a person who's likely to disrupt a flight?

C'me on, calm down, security agents at airports all over the world are known to behave in bizarre ways, be that in the US, Greece, Germany, Patagonia, you name it. No need to blame Greeks for that, they did not set the trend, they followed it. These guys are just doing their weird job, and if every passenger who is "complaining" (only you and they know what you said to them after they grabbed your saline solution bottle) and arguing, security controls would double the time they take today! Even triple if they followed the ideas of point g) above.

Sounds like security worked as it was designed, and the OP is raising a hissy fit over the fact that they enforced the rules on him/her.

I only pointed out to them that I'd taken the containers on numerous flights, including through ATH and CHQ within Greece.

They wanted me to take my camera and lens out. Whatever, I didn't say anything to them about it.

They didn't have me remove my shoes and only once had to remove my belt out of the 3 times I flew out of Greek airports.

There are no consistent standards.

And no, I didn't have cross words ("hissy fit") with them at all. I am pointing it out here an instance of a standard being applied that I've not seen anywhere else.

And everyone else has been pointing out that the 100ml/3.4oz container standard is routinely applied day in and day out across the world, including within and from the USA. It is difficult to tell a 4oz bottle from a 3.4oz bottle visually unless you read the writing on it, but sooner or later a security operative somewhere was going to do that, and you were going to lose the bottle. The regulations relate to the container size not the amount of liquid in it, part-full bottles have to comply with the size regulations.
Why not name and shame the US company who sells something as suitable for air travel when it has been against TSA regulations since the day the liquid restrictions started? Unless of course they meant it was a convenient size to pack in your hold baggage?
It is convenient for travellers if security everywhere checks the exact same things each time, but it is also convenient for terrorists since once they've found a way of getting explosive or weapons on board, they know it will work. By varying unpredictably which items they check in detail, airport security tries to make it more difficult for would be belt bombers, mix-on-board liquid bombers, carriers of exploding i-Pads and so on, without the whole air transport system grinding to a halt because every single item is completely checked everywhere every day.

Unisol 4 is the product name.

Alcon apparently just discontinued it.

I'm looking at an alternative called Purilens. They also sell in 4 oz bottle and say they have a little card explaining that it's FDA-approved as a medication rather than as cosmetics.

I repeat what I wrote above: using a saline solution stored in a "large" container over a long period of time, only to put a few drops in your eyes every now and then, is asking for trouble. I don't know the US pharmaceuticals, but if you lived in Europe I'd first have a check-up with an ophthalmologist and ask him to prescribe you "artificial tears": they're also saline solutions but over here in Europe they're sold in small containers of a few drops each, thus no risk for infection. More expensive than the saline solutions you mention, of course, but after all it's your eyes. No charge for this piece of advice...

I'd add to this professional advice that just because a package has a little card saying something is approved as a medication, this will not have any effect on security personnel.
They will only accept it as a medication and so exempt from the liquid container size rules if you can prove it was prescribed for you by an appropriate medical professional. If you really must take saline on board in quantities larger than KLouis recommends, just find a 3.4oz bottle instead. As this is the agreed world standard travel size, you shouldn't have any problem finding one.

ATH is the only airport that consistently confiscates any toiletry that is over 100ml. It really is amazing. 101ml? They will find it and snatch it away from you!

Yes, security checks in ATH are extremely pedantic and b... breaking but, at least, they're very consistent. Thus, if you get caught with 101 ml bottles every time, what can I say, τό δίς εξαμαρτείν ουκ ανδρός σοφού!

I had a bottle of Aveda hair product (maybe 110 ml) taken at CPH, and I noticed others in line having similar treatment. YYZ also.