In 1979, I sat down at my favorite bar and ordered the usual. An old timer sits down beside me and we start talking. He has some incredible WW2 fighter pilot stories. After a while, I realize this guy is either a famous WW2 ace, or a world class lier. He gets up to take a leak, and I ask the waitress (a friend of mine), “do you know this guy ?”
"Yes, she says, that’s Pappy Boyington, he flew planes in WW2."
When he came back I paid for his next drink, and sat there for hours listing to him.
Wow! That's the best!
I'm pretty sure I've never had an accidental encounter with anybody famous. Living a the end of the pipeline doesn't make chance encounters too common.