Yes, on New Year's Eve, street vendors in NYC will sell them. That's because once you get into the Time Square to see the ball drop, you are stuck there for many hours. Unless you want to lose your place. Once you leave the area, you get to the back of the line.
It's something that everybody should do once. But only once.
I like to party as much as the next guy, but I’ll have to admit, such a thing NEVER crossed my mind.