@Iñigo ***********
That you think it is insane does not make it not normal.
It is not typical Thai, most countries tell you that you have to take source documents with you, and also check them.
It is perfectly normal, and your argument that once checked, means extra checks later on are useless is just an invalid argument.
You can read here a lot of stories of people who think they don't have to comply with any rule the moment they are approved.