Actually in golf there is a specific rule in place to prevent cleaning of the ball except on the green or in between holes. If you get a big mud chunk on your ball you have to play it as it lies even though it may affect the shot substantially. It's called "the rub of the green". Every once in a while the PGA Tour will use their own rule called "lift, clean, and place" if conditions are exceptionally wet. That usually sends scores plummetting and you would never see it played in a major. Pool is an entirely different game however so an argument can be made that cleaning of the balls by a referee should be allowed as it has customarily always been allowed, but I believe it should be all or nothing.
