A little fighting is good to clear emotions in a game.. in an NBA game players hold back until theyre really sick of whats ever going on and they explode causing a big scuffle spreading across the court
There's ettiquette in hockey fighting.. theyre on skates so its always in a small stretch of ice, they throw punches and grab/block.. its pretty simple on skates. First to go down and fight is over. No 'retaliation' or gang jumpings. Its fair and settles the dispute and makes sure pent up rage doesnt make a player do something he may regret.
When youre out on a bball court you could have these guys chasing each other going everywhere, diving at each other, running around.. its just too wild and uncontrolled. Plus there would be no ettituquette like in hockey.. and they dont have pads and helmets on so it would likely be more dangerous. Just not a good idea for basketball based on how it operates