I once signed up to XBox Live with my credit card. Soon afterwards, I realized that the online gaming "community" left much to be desired and that they didn't even provide dedicated servers for my games. So I decided to quit. But they purposefully do not provide an unsubscribe path through their user interface, you have to call them, wait on hold, and provide your whole credit card number + CCV to unsubscribe.

I have no doubt some MBA at Microsoft thought they could shave a couple percentage points off their attrition rates with this tactic. I sure as hell will think twice before I subscribe for any other Microsoft service again.