American consumers have a cornucopia of plastic cards in their wallets, bearing the familiar logos of Visa (NYSE:V), MasterCard (NYSE:MC), Discover (NYSE:DFS), and American Express (NYSE:AXP). But plastic aficionados, beware: Soon, you could get slammed with a fee for practicing restraint. Priceless.

Bloomberg reported that Fifth Third Bancorp (NASDAQ:FITB) is trying out "inactivity fees." That's right -- some cardholders could rack up fees just for having the card in their wallet, but not using it. This could be a sign of things to come, as other lenders also experiment with fee structures.

We all know that profligate spending on credit helped fuel our recent economic crisis. Now, banks are dealing with higher delinquencies and defaults by finding ways to make up for anemic revenue. However, punishing responsible customers might not be their brightest idea ever.

Do concepts like this give you a warm and fuzzy feeling about financial companies' bright future? Or do they just make you want to dust off the ol' pitchforks and torches? Sound off below.

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Alyce Lomax does not own shares of any of the companies mentioned. The Fool has a disclosure policy.