I'm a UK citizen and travel to the US for tourism. I've been singled out, last time was at Newark when the guy couldn't understand that I just like to travel as a hobby and was quizzing me about previous trips I'd been on.
I think I was annoying him by going into too much detail but didn't want to seem evasive either.
He ended up closing his desk and walked me through to customs to inspect my checked bag with employees there. He realised then that he hadn't properly stamped me in to the US and I shouldn't be in that area - I could hear the conversation. I was asked what I thought was so funny, the answer to which was I'm glad I took a piss on the flight before landing. They were not amused.
Meanwhile, the customs agents wanted to see in my bag but wouldn't let me go to the carousel to get it. They relented when I asked how they'd know which was mine if I couldn't go there
The trip before that I got through immigration at JFK quickly, collected my bag and one customs guy said "get him" to his colleague and I was searched for a few minutes there.
It comes across as really unprofessional a lot of times, officers can seem to possess more authority than intelligence and it irks me that - conversely - US citizens can visit the UK with just a scan of their passport on a machine of an ESTA equivalent.
​​​Doubtlessly, others will have it worse..
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