Great idea, but the biggest problem is that it incentivizes users to pay only with credit cards. For a small restaurant owner or retailer, those bills can go upwards of $10,000-20,000/month, and could be incredibly detrimental for, say a frozen yogurt shop.

Now, the ease of use will be a big part of this (just using your own credit card), and may alleviate some of these troubles for the retailer from a training perspective, but this is yet another potential for business owners to make bad decisions sacrificing long-term profit in exchange for short-term growth.