I find the argument that competition breeds violence and thats ok cause it makes more of a spectacle and these guys get paid for it quite curious.
Take my line of work, I am an IT contractor and obviously get paid for this. Should I go start a fight with the next guy who beats me to a contract? Or the guy who cuts in line in front of me at the Supermarket?
I enjoy RC racing, and passion and competition is part of it. People get heated and competitive, and that I feel adds to the whole experience. But when that breaks into physical violence, well thats totally crossing the line. It is against the law and all. Arguing the violence is all "part of the sport", well perhaps you should take up hockey.