If I had an mmo, I'd start a campaign where you have to find golden tickets irl throughout the U.S.A. (hidden by the ad campaign team) and make it so you have to deliver them to 7-11 clerks, who would give you a voucher for gold. Then, in the game, you redeem the code and buy stuff for your avatar like some gamer apparel, a new mouse, a new keyboard, ram upgrades, pizza, etc. There isn't much to do in the game but sit in a chair and play WoW. You redeem more codes for gold while you watch your avatar sit in his room and progressively get fatter as he plays more WoW. If you try to leave your house in the game, werewolves pretty much eat you alive.