Airsnoop,
I fully sympathise with you.
I'm fairly well travelled and in my experience it only seems to be the Americans who hire the most obnoxious, rude, unsmiling and impolite people they can find for their immigration and customs staff.
In the last 3 years I have flown into America 4 times and each time was the same. I once even had another American passenger apologise to me on behalf of an immigration officer after particularly shoddy treatment.
What infuriates me even more is that once you get into the country, the American general public (although I guess it depends where you are!
) are amongst the friendliest, most polite and helpful in the world.
I think it's just a power thing. These idiots don't have the brain power to do anything else and when they get given a uniform and a big shiny badge, it elevates their ego to the extreme so they think they're more important than they actually are.
Rant Over.