I used to get into a lot more when I played sports. But I've had a number of encounters. I would actually say I've witnessed, been directly there, in the fray, but gotten by without much involvement and participation on my behalf. I've always been in groups when fights have occurred and let the biggest kids in our group settle it, or the crazy ones. In middle school and the early part of high school I used to get into a bunch. I got suspended once for that specific reason.
I think there is still a decent amount of physical altercations, I guess people just don't put themselves in situations in where the threat, or prospect of settling it in that manner is there. My friends in Canada when I visit down there always get into fights. In fact back in elementary and middle school there would be fights everyday. And I'm not talking little bitch slaps.