Well, that's absolutely not true Ai Bang. Now, your assertion might be correct if you said "video game" but you didn't. You can get banned for being a jerk in sports, and in other games as well. There have been players (and owners) banned for unsportsmanlike and offensive behavior in baseball. Marge Schott was permanently barred from baseball, as owner of the Cincinatti Reds, for racism. In Magic the Gathering, you will be given game losses and DCI bans for unsportsmanlike conduct. In any face-to-face game, there are certain standards we are expected to play by. I am not allowed to throw down my Jace the Mind Sculptor, stand up from my seat, and make thrusting motions with my hips while screaming "Get Jaced, motherf******". I would be given a game loss, and probably be lucky to stay in the tourney. Now, I realize that is a slight exaggeration, but your assertion that people don't get banned for *being a jerk* in other games is false.
For those interested, the "Get Jaced" story is actually real, as a player did that at my LGS. The owner was very firm that the next time the guy made thrusting motions with his hips, he would be defenestrated crotch first.