How to NOT steal a credit card
Tell your customer that there's a problem with the card, then go next door and buy such an enormous amount that the retailer calls the customer to verify the order.
There are smarter ways to steal credit cards in restaurants, you know...
Since this happened in Shanghai, let's take bets on how quickly the Chinese government blames the decadent western bourgeois pig-dog capitalists for introducing credit cards to the agrarian peaceful people's paradise of the Middle Kingdom. Because you know, it is always America's fault.