shake on it

There's something I noticed at baseball games over the last few years that has really bothered me. At the end of the game, the winning team goes out to shake hands with...itself! When did this happen? I swear within the last ten years I remember seeing both the winning team and losing team go out and shake hands after the game. It's one of those small but significant signs of good sportsmanship you learn in childhood that continues up through every level of sport. Or did. Where did it go? And when did it go? And why?!

I noticed it again when I was at the Olympics - the teams did, thankfully, shake hands with each other afterward. Good enough for the Olympics but not good enough for major league American sports? come on now...