My kid has been on 4 recruiting visits. On all of them, he was exposed to partying to some extent. One was fairly reserved -- the team was just hanging out in an off campus house together and drinking a few beers. Another was a bit bigger, as the girls team was there as well. A third they just played some video games. And, the final one the team was playing beer pong.
I have no idea if my kid was an observer or participant, although I hope he was smart about it. But, that said, I feel it is really important on these visits that he gets a sense of what the team culture is like, and I think this allowed him to do so.
The only problematic thing was for two of the visits, he was asked to fill out a form at the end saying he wasn't exposed to things like this. He said he went ahead and lied on the form, as he didn't want to get the team in trouble, as he liked them.
Anyway, I am not saying this is right, but it is normal in my experience. I just hoped my kid didn't do anything stupid -- probably not unlike what I'll be hoping for when he goes off to college next year.