I've never had problems with people at a Chiefs game. I've been to about 10 games total.
But I've had numerous issues with people at Royals games. I've gotten to the point where I will not go to a game on a Friday or Saturday because everybody just wants to get stupid drunk and act like a bunch of retards, and not even pay attention to the game. Leaving the parking lot after a Royals game is always a ****ing mess. And I'm not talking about the driving part.