Temporary anarchy

I am amazed sometimes at how people act. It seems that often times people today are just waiting for an excuse to cause mayhem. This weekend hundreds of college students started a riot after the University won the national title for hockey. These actions are not unprecedented. In LA, there are always riots, after court cases, basketball games, afternoon tea - anything is an excuse to riot. I don't get it. Is our peaceful society such a precarious thing that it can be toppled, be it temporarily, at the smallest occurrence? Is the population so frustrated that, whenever possible, we create a temporary anarchy to release our pent up angers?