[wwwflyer]

Sorry to hear you had such a bad day. We've all had those days.

Airlines.....ALL Airlines may deny boarding to anyone for any reason. I would think that if a passenger is being disruptive on the ground the agent would be less likely to board that aggressive behavior. It can be pretty scary to have a disruptive and aggressive passenger at 35,000 feet in a pressurized tin can zipping through the skies at 500 miles an hour. I know personally I would rather see that person kept on the ground and cool off before getting on an airplane. Why would AA pay for your room and board? It was your own mouth that got you into the mess you were in.
Good Luck in the future.