Winning a fight does not change the facts surrounding an argument. Hulk Hogan could beat up as many scientists as he likes, but that won't change the gravitational constant of the universe, even if he disagrees with the scientist's conclusion. Capacity to win a fight ≠ your side is right.
See my other however I posted. AFAIK 2 people can just go to a amateur boxing/wrestling event and beat each other up for whatever reason they like. As long as a release is signed, they can do whatever they want in a private space short of killing one-another.
If you're just saying that 2 people should be able to fight over who get's the last chicken wing (or other such random thing) and not in a legal or factual matter, I'm pretty sure you can do that in private, there's plenty of amateur wrestling/boxing clubs, and some of them won't care why you fight.