Not all high belts suck. There are as many rage quitters with low belt rankings as there are high belt rankings.
Rage quitting will still get you out of losing belt points if you the rage quitter is the host. If the rager quitter isn't the host, though, then the battle completes. He'll still get stuck with the loss. Rage quitting giving him -99 will automatically put him into fourth place. You lose more belt points in fourth place than you do if you were in second place.