Content delivery systems have gamified games by building their own level and achievement systems. Kongregate and Steam are two that I use. Kongregate flash games may have levels, points, and achievements, and then Kongregate itself has badges, points, and levels, and now pets that may appear in games. Steam games have had achievements for a long time, and now Steam itself has a trading card mechanic that leads to crafting, badges, and levels.
Steam has started tying its seasonal sales to those. In past years, you received the seasonal achievement for gaining achievements, voting, shopping, and otherwise using Steam. Those are now mediated through trading cards (and those trading cards now incinerate at the end of the event, rather than sticking around for latter day trading, which I think was uncalled for). And crafting completed sets of trading cards during the seasonal events awards seasonal event trading cards.
I am sitting on five sets of cards and waiting for the next seasonal sale event, because it will be worth marginally more to cash them in then than now. I am gaming the gamification of games, and the absurdity alternately amuses and irritates me.