I think the opposite is true. The hardware is almost a gimmick to push what is otherwise a potentially powerful service.

The theory behind this app is that individuals are now empowered to take credit cards for anything they previously would have had to take a cash or check for, which is increasingly important in our society where credit cards are becoming the normal way to pay for things.

As for the hardware, it's a pretty old trick. Though I don't know any of the specifics of this device, you don't need to look any further than your graphing calculator to see the idea in use.