Because logic is hard, man.
It's probably because they lack self control. They already demonstrated that they lack it in WoW("flight is in, thus I must use it"), so it isn't a stretch for them to not have any here.
I thought that maybe they were lying about not wanting to ground mount because of flying being in the game. Now I see they have some sort of mental block where they can't actually control themselves. They need their hand held in WoW, and they need their hand held on the forums. Makes complete sense now.