I had a gigantic paper airplane handed to me while I was in the stands at a Gator Growl in Gainesville once. My date and her friends were like " Go ahead, you have to try and get it on the turf!" I had seen one or two take flight earlier and thought, fuck it, sure, when in Rome...right?
10-20 seconds later I have 4 very overweight, very irate cops up in my face screaming about how they're going to throw me out of the stadium by my hair. Turned into a yelling match were I was saved by a pair of my girls friends who were quite drunk (and also very overweight!) who told the cops off, somehow sat on me while allowing me to still breathe, and told them they weren't allowed to take me away. It worked too, they left but continued watching us.
So unless you blend in perfectly, or have a pair of huge drunk black girls at your side for crowd control, I would skip on launching those things into crowded public areas. Turns out you can hurt someone if they catch it in the face. Just fyi!