When you go into a store that offers their restrooms to paying customers only but you sneak in a deuce and a piss and evacuate the premises immediately before the cashier/manager notices your shit and run.
I stumbled into a convenience store that had a “Customers Only” sign on the bathroom door but I didn’t have a penny to pay but had to make a large deposit so I committed a “shit and run”
Taking a massive, hellacious dump in someone else's bathroom (especially a stranger/acquaintance), then leaving swiftly and pretending that nothing happened.
Person 1: Hey man, why are you in such a hurry? We just got here ten minutes ago?
Person 2: Get your coat. I just took a massive shit in this dude's bathroom, and I want to get the hell out of here before he finds out it was me.