To quote General S. Patton: The object of war is not to die for your country, but to make the other (bleep) die for his.
In this case, its a win to prevent people from getting max rewards.
in the context of a free anime game that is incredibly petty, which is exactly why you are correct. People would rather use kushi, have about as much fun as getting a lobotomy and waste both your time and theirs instead of using their characters and treatng this like a game