It's really simple. I pay for this game every time an expansion releases. I also pay a monthly subscription. These costs should cover the game's costs and development. Any item/mount/transmog/whatever put into the store is something that could have been put into the game with a piece of content attached. The new transmog? Could've been from an achievement or questline. Instead, it's in the shop and you just buy it. It's possible content removed from the game for the sake of making money, which I dislike.