Simply based looking like I'm from a part of the world where life is not as difficult seems to be enough for a number of people living there to take a chance. I could also feel how I was the focus of attention of many who did not dare but were considering making the move. A very strange and creepy experience.
And that was in the streets and public places, I'd expect that in the context of a private party the teenagers who managed to get their way in to be daring enough and trying harder, so I guess we have different views based on different personal experience.