There is one example I usually use every summer with our softball team. We have a mix of guys, many that went to the local suburban public school, some from two private schools - a good mix. The discussion usually comes up once a summer and I always say this, "Hey, at your private schools, did you guys have bouncers?"

Private school guys: "What? What do you mean bouncers?"
Public school guys: "You know, to break up all the fights and stuff."
Private school guys: "What fights?" '

I went to Marquette High - in my four years I saw one fight. One, and it was a weak one.