When I stopped playing WoW, players could collect pets by redeeming tokens/codes from blizzcon or other real world fan or collector activities, but today there is an entire mini-game surrounding battle-pets which can be collected in-game and also purchased via earned gold or simply cash. Additionally, Raid or PvP gear sets can be supplemented with purchased "cosmetics" and "heirlooms" which again can be purchased through earned gold or through the store with cash. It seems like every side-game activity has some kind of purchase available to "speed up" the time it takes to "earn" the appropriate currency required to redeem the reward. I've been out of the gaming loop for far too long to really see how bad it's become, but it was absolutely shocking to see it.