Do you mean it's your customers who are being deceitful by charging back a service after they've used it (as mine do). Or do you mean that you have customers using stolen credit cards to pay for your service and that the chargebacks are happening when the card owner discovers as much?

I haven't seen any evidence of that second case happening with my users (apart from one incident where card thieves discovered my "update your credit card" workflow and used it to sanitize numbers for a few days before I fixed the loophole). But the first one happens all the time.

It'd be adorable in a way, as I'm sure the people doing it think they're totally getting away with something. If, that is, it didn't jeopardize my ability to continue charging credit cards in the future.