So, is this a bit like "clubs that have accepted my fake id, thus proving it is genuine"? I'm assuming customs are accidentally accepting passports that were printed by internet randos.
Correct, and generally known as ‘passport control’ in Europe and many other countries.
I think ‘immigration’ is primarily used by English speaking New World countries which historically had large scale immigration (as in, settlement) programs after the world wars—although I don’t have a definitive source for this.
Given the countries they cite as having accepted it (decades ago!) , it looks mostly useful as a tool to check whether a baseline level of border security even exists.
