Speaking of Google Wallet, there's an idea I've been thinking about. Google lets you use your phone to charge on your credit card, but what it actually does is charge a virtual MasterCard debit card, and then Google charges your credit card. The receipt on the screen shows you the last four digits of the virtual MasterCard.
Has anyone tried buying VR at a store that doesn't accept credit cards using Google Wallet? The store should think it's a debit card and you can give the last four digits from the screen.