That applies to most of the staff at ATH I have to say. There are some exceptions (I had some bad experiences when flying LCC out of Athens) but overall I find the check in agents very nice and helpful indeed.

Great example: I am flying ath-ams today. Booked through Paris with 1:10 transfer time. The AF flight to Paris has 45 minutes delay so I went to the ticketing desk - and I didn't even have to explain what I was hoping they would do. The guy instantly rebooked me on the direct klm flight to Amsterdam.

Another time I arrived a little early - and after asking they rebooked me on the earlier flight for free. Even though I only arrived at the airport 30 min before departure of that flight with check in already closed!

These things are rare when flying within Europe. Common sense says that these things should be standard..but I dare you to try the same at AMS, CDG or other major airport. They will send you away laughing about that you dared to ask.

Of course it helps that I am flying out of ATH bi-weekly for many years, so many of them at least recognize me. But I don't think that's the main factor here

One general rule applies at all time. Be nice to the agents, and they are nice to you. When you start your question with a 'hi how are you?' instead of pushing your demands and/or wishes, you will see that almost anything can be arranged. (Within the boundaries of what is allowed of course).