Funniest Place For This To Happen?

Came across this on another blog and it got me thinking about marketing and also surprises. I think crazy stuff like this would definitely get people talking about whatever store they were in - maybe this was scheduled. But maybe it wasn't. Maybe it's just a plain 'ol flash mob (check some other ones out on You Tube like this) Either way, I think this would be hilarious if it happened at a graduation ceremony - even better, a law school graduation.

Where do you think the funniest place for this to happen would be?