^ This goes back to my asshole comment, earlier. I bet they asked him to leave per the terms of the ticket agreement, he refused and made a stink during the game from his seat, and he got escorted out by the cops. Once you don't leave someone's private property when ordered, it's trespassing.
If an establishment asks you to leave and you refuse while carrying a concealed weapon its a third degree felony for armed trespassing. In fact even though you have a right to carry it actually makes sense to be less of an ass because you can always get into more trouble without even firing.