It's only natural that when someone smiles or waves at you, you automatically respond by smiling or waving back to the friendly gesture.
Maybe that's why it took two hours of 400 leering Hispanic and African-American half-naked, tatted criminals to realize I should not respond.
Anyway, I hope no one I know goes to jail. And if you do, I'll teach you how to make nunchucks out of plastic sandwich wrappers and what to do if the Mexican Mafia tags you as a "green light." And how to make your own foul Pruno.