...the Sha are only a problem...and thus the Mantid and Yaungol are only a problem...because of the Horde and Alliance.
It's like somebody starting a fire in someone else's house, the owner unable to deal with it, and then the same person comes back and puts the fire out. Yeah, thanks for putting it out, but you also caused it in the first place. You haven't done them a favor, you've just cleaned up your own mess.
And then the owner finds the arsonist breaking down part of their church/holy place because they want something underground beneath it. They have every right to be pissed at them. They don't exactly like them in the first place.
If the Shado-Pan weren't kind of preoccupied across the rest of the continent by problems we caused, I'm sure they would have had much better success with the Mogu. Contrary to the belief of our resident Orc apologist Thrassk, the kicking of the Horde out of the Vale has nothing to do with the Alliance whatsoever. Not only is it not an Alliance faction doing it, but the Alliance doesn't take part in it, and they can't even see the scene (To my knowledge. Unless we can hover over the Horde's shrine and see it. And if so, I would probably assume it was an oversight). Its just another nail in the "Garrosh dun fucked up" column. Its that simple.