Well put Vix. Also imagine, you're a 19 year old girl and you get a laminate that the famous singer wants to meet you, one could imagine that there's a naivety and maybe an insecurity or nervousness of not wanting to turn him down and decline.
People come to concerts to listen to some music and see a little entertainment. I've never understood this idea that women in the audience are desperate to fuck them. But you hear these stories from so many rock bands of roadies going out and cherry picking girls from the audience and most of the women oblige. I think a lot of it is probably pure pressure and just the utter surprise of the situation and not knowing how to react.
Of course there's also the women that go out, flashing their tits and desperately hoping to get picked to fuck one of the band members.
I was partying once with this chick who got picked to go backstage to bang one of the guys from Steel Panther and she did... I mean, really, Steel Panther does this shit and people oblige? I guess everyone wants to live that rock star fantasy, musicians and fans alike.