The Washington Bullets/wizards had a famous heckler Robin Ficker. He wasn't some moron. He was a very successful Washington attorney. He had season tickets behind the opponent's bench. Charles Barkley was so impressed with how distracting the guy could be. He flew him into Phoenix for a Suns-Bulls series and got him tickets behind the Bulls bench.
I've never seen fans in any sport tossed unless their speech becomes offensive or they are standing and blocking fan's view and refuse to sit.