Sometimes people fart in public. Not on purpose sometimes (though not necessarily by accident sometimes either), but it happens. What are they thinking just before or after the deed ...?

"Oh, here's a crowd; now I can't be pinpointed."
"Damned burritos."
"Okay, my butt muscles are tired now. There's no more holding this one in."
"Damned dairy."
"Oh, no ... this is gonna be a doozy."

Go on, I know you got some funny ones (from experience)!