Well we play WoW to have fun, which means hunting fun items or mounts for most, as you all know the raid playerbase is like 500k ppl out of LFR (If that) so the rest 8 million or so ppl do what? Do LFR and hunt old items/new ones from CM mode gear/old raids and hunt down cool looking mounts. Now if half of the next mounts/gear introduced are Ca$h $hop items then that means you ruined the ppl's fun in the game by 50%. Many may use the store now but do you really think everyone will buy every little thing? There is a limit to how much one will spend. Finally there is one more thing made from that, less quality content in game because... why would you buy something ugly when you can get pretty stuff in game, I'm pretty sure it will be the other way around with ugly/reharshed stuff in game and unique cool looking mounts in store. We can already see the trend with t16/s14.
Most sets are ugly (of course pvp never had really that many nice sets anyway) but t16 is seriously horrible, nearly no class tier resembles what they really are, Paladin tier for example looks like a walking furnace lol... there are like 4-5 tier sets/season sets that are decent out of 22. And please don't start the "good looks is subjective" crap. Most ppl have been negative about them, both ppl in forums and all ppl I know in game. Just because we don't bow our heads and just say "Oh look so cool looking!" and critisize the armor sets for a game we love to play doesn't mean we have a bad taste or that we hate blizzard.
Also if you ask me why I haven't quit this game, I'm sorry but I've already did, I just feel the need to contribute to the discussions for a game that keeps getting more and more rotten... and here I thought that MoP was brilliant but then blizzard ruined it with their new sparkling cash shop...
edit - I bet corrupted ashbringer/transmogging legendaries will be a store feature! Don't be surprised if it happens! :O