That's funny! It had to happen some time, eh?
Thankfully (or not, I don't know) I don't ride with people who will tell me my butt crack is showing. I don't ride with people at all, so if a stranger ever gets enough gumption to tell me they see my butt crack, I'll know it's REALLY bad. Otherwise I'll just keep wearing my shorts until my big ol' butt wears a hole through them. I'll likely have someone telling this same story to a friend of theirs and making the both of them laugh.