Because the loyalty wasn't for the Slasher if I remember correctly, but so people could tame the Bane Dragons there without having people trail Hell Hounds onto them, or worry about Slasher coming across and killing them and... it was just a way to allow people to actually use the content more easily whilst it was there. Of course, the Bane Dragons have gone as well now... but still, if it helps a bit with fighting Slasher, I can't see why it should be taken out.