But would the customer who wants to pay wth BitC using NFC technology accept that he must wait for some confirmations before he can take his merchandize home? And would merchants, especially large stores that go to substantive effort to streamline checkout processes, accept a payment protocol that by design adds a one hour delay (IIRC, people seem to regard six confirmations as definitive proof of payment, and the work factor is adjusted to give one confirmation per ten minutes on average) to every checkout? Even requiring just one confirmation would mean that a supermarket cashier could only process about four or five customers per hour if you want to keep the process sequential.