Actually there are, not everyone does, most people who play games don't, but, there a still a lot of gamers that will use games to relieve stress. There was a violent flash game made by adult swim on cartoon network, called "Five Minutes to Kill Yourself" which, when advertised on TV, actually mentioned a way to take away stress, the game was very popular and well received. People love punching things, throwing things, hurting others, ect. when angry just because people naturally get calmed down by such actions. In games you can do all of that, and there many people who do all of that (not a large percent of the game community, but the game community itself is enormous). This can largely be contributed to online games, because, a lot of people will say they want to kill X person or punch Y person when angry, in online games like street fighter, they can actually kill X person or punch Y person without consequences or actually harming more than the person's character.