UK versus US immigration
I'm a Brit and hold a U.S. visa (temporary resident) as I work for my company both here and there. I live most of the time in the UK.
Compare and contrast: the last time I went to SFO, I waited for about ten minutes, was greeted with pleasant courtesy, and on being handed my passport the immigration officer said "welcome home, Mr xxxxxxx".
On my return to LHR about ten days later, I waited in line for 30 minutes with the rest of the EU passport holders, had my passport looked at, all the while the immigration officer did not speak one word to me, while he continued a conversation in Hindi with his colleague. I was waved through.
This, in my experience, is the norm.
Guess where I feel more welcome?