Just to trade anecdote for anecdote: I’ve ridden lots of greyhound buses, and never once been asked for my passport in the US (or any form of ID by a police off

Just to trade anecdote for anecdote: I’ve ridden lots of greyhound buses, and never once been asked for my passport in the US (or any form of ID by a police officer; since I’m a US citizen, it’s not like I would have had a passport to present). But, as it happens, I have been asked for my passport by British authorities on a train ride once in the early 2000s. Presumably if I’d had a British accent they wouldn’t have expected me to have a passport on my person. I suspect both of us experienced relatively rare events!