I think my most unique pro encounter was at ASR a while back when I went to see the premiere of D-Way's bonus DC part.
My buddy and I sat down a few seats from some older lady. As we were sitting down, I was thinking, "Weird. I wonder why this older woman is here. Like, does she run a local shop or something? Who is she?" And then a few minutes later, she looks at us and says, "Hey, can you guys move down a couple seats my boyfriend, my son, and his girlfriend want to sit down." We say, "Sure. No problem." and we move over a couple seats. Then some older dude, Danny Way, and his girlfriend all walk over and sit down. I ended up sitting a seat away from D-Way during the premiere of his gnarly mega-ramp part.
This is one of those moments where I think to myself, "Fuck, I am so glad I didn't act like a piece of shit and be a cool-guy dick for no reason." I can't even imagine how wrong things would have turned out if we were anything but polite.