The only place where I've seen any real life hazing was sports related. I was hazed and later led many a hazings and am a better person because of it. It's a rite of passage and way to weed out those who, as stated above, either aren't cut our for the sport or don't really want to be there. When you're young, your team or crew are your family, so you're not going to just let anyone join. Young kids look up to you and want to be a part of what you're in, but you don't just accept them, they have to earn that.
By hazing I'm talking about constantly ragging on, encouraging them to do silly things or dares, asking them to do petty tasks, stuff like that. Nothing like the caricatures you see of it in movies. I'm still close friends with the guys who hazed me, and I made good friendships with the younger guys I hazed. Having said that, there were kids who weren't on board, who resented the system, and the moment they made it clear they didn't want the treatment, we backed off. Of course though, they never became one of us.