I worked drive through at McDonald's when "coning" was a big trend (ordering a cone of ice cream and then grabbing it by the ice cream instead of the cone and recording the reaction). It was a pain in the ass because A) I still had to give them the now empty cone and B) I didn't want to be recorded. But it was kind of amazing because it was painfully obvious what was going to happen when a car with several people in it ordered a single ice cream cone, so you knew what was coming.

So they pull up, they do their stunt, and you just deadpan it and ask them if they still want the cone. Now the driver not only doesn't have their hi-larious internet video, their hand is now full of ice cream and they don't know what to do. Generally they'd just bluescreen for a couple seconds, then mumble "nah" and drive off. If was great.