Why ask for 'date of issue' on passport
 

Some visa applications for most countries as for passport number, date of birth, name, etc.

Why do they ask for 'date of issue'? What does that have to do with anything?

It could help them decide if it's a valid passport or not, for example when the colors were different for the covers for those issued in these years, things like that. It also confirms the expiration date, and identifies how old the picture in them is.

But as the date of issue is recorded on the passport itself, which is submitted along with any application, surely it's a little redundant to make the traveller fill it out too?

Then again, in these days of barcode readers and swipeable passports, making the traveller fill out anything at all is pointless :mad:

I guess this is my real point...why fill out anything at all!!

What about those immigration forms in foreign countries where they ask you to repeat just about all the information on your passport like DOB, gender, place of issue, date of issue, date of expiry? Even super-efficient Singapore where passports are machine-read asks for these redundant data on the arrival card which the immigration officer never even bother to look at.

I think the reason for this is inertia.

The problem is not all countries have machine-readable passports. The fact that the US now (de facto) requires these and other countries have to follow suit is, quite possibly, the only good thing to come out of the terrorism brouhaha...

Because it's a document that can be brought into court and readily used against a foreigner for perjury/false declarations to a government official if the need so arises.

Some countries want to know date of issue to make sure that your passport will not expire within the duration you are legally entitled to stay. Have been challenged on this once when my passport was due to expire in 79 days - presenting a copy of my return ticket which was in 3 days seemed to mollify the immigration agent.

I think I'll need more information here. I have a very hard time remembering the last time I lied on an immigration card. I do check "honeymoon" for "purpose of trip" every time I fly to Hawaii, and I couldn't resist selecting "agriculteur/pecheur" for my profession on my last Tahiti trip, but I don't think people so routinely make false declarations on their immigration cards that these documents provide significant backup for detentions and the like.

Indeed, but as you said, not everyone is there yet. The forms still have to be filled out by all travellers because there are still some travellers who don't have machine readable passports, especially from countries like Pakistan, Afghanistan and so on.

Besides, even some passports from European countries aren't machine readable. There are so-called last-minute passports for people who don't bother to check their passport's expiration date until three days before they fly, and these don't work terribly well with the passport readers.