Credit card point schemes are a familiar form of gamification. They obviously have some effect on puchase habits, as pointed out by Jennifer at “For The Win” (In Real Life: Credit Cards.)
The interesting aspect for me is that they are lacking in some key areas that we associate with a more modern gamified approach. Credit cards may have originally had a very rough analogue of levels in the form of “gold” and “platinum” cards, but these seem devalued when any card issuer can go for a gold or platinum appearance for a common card, with no need for the bearer to achieve any particular levels of wealth or spending.
Also missing is the social aspect that we usually associate with gamification. Purchase, payment and debt history is held up as a big personal secret, so there are no leaderboards, no challenges or achievement badges, no competing with friends, or anything to engage social networks with the card as a brand in itself, rather than just a proxy for affording other brands.
It seems entirely likely that the first credit card company to find a way to tap in to a broader and fuller range of gamification techniques could make a very large amount of money.