For me, the problem with the store mounts isn't that Blizzard is using them to make extra money, but that they limit the options of what can be available in game.
Some mounts, like the Celestial Steed and Mystic Runesaber, are generally disconnected from the in-game races, factions and environments. They stand out as store mounts and they are fine like that.
But more and more of them seem to be plucked from the world, greatly limiting what could be some very flavorful and cool rewards from factions and other in-game sources. Starting with the Armored Bloodwing, which was the bat mount people have been asking for for ages as a troll or undead flyer, up to the WoD creatures that are found all over Draenor but can only be bought from the store.
I'm wondering if we can find a compromise here that allows Blizzard to make extra cash from selling mounts without actually taking away from the game. So, would you still buy a store mount if you knew that a different version already existed, or would later be made available in game? I'm curious what mount buyers think.