So does pet battles. But if you removed it now a lot of people would be mad.
Look the bonus stats are very minor. And you should not be going "I wanna 100% a mmo to the extreme" the whole point of a mmo is to last long. Its like trying to explore all of mine craft... it's possible but is it worth it. Get your BiS year that's fine. But don't scream at blizzard cause getting the BiS gear with sockets. Leech/avoidance. And highest item level is something that should be easily possible... if you want to fully 100% something it should take a long time. I find it funny how people complain getting epics is too easy. But then complain when blizzard try to make "epics" harder to get by added these and making them hard to get