I enter grocery store, choose groceries, etc. Cashier scans items, user notifies them that credstick will be used. The vendor unit logs this individually and also adds the amount to its daily total, and passes a verified signal to the cash register, where a receipt is completed. I'd like to know. On vendor end, see total, press 'credit stick' on cash register.
Press verify total on personal vendor unit.
If something becomes of this, I'd like credit for the idea, absolutely. I'll be right pissed if someone up and patents this, hides the tech, and makes a titload of cash off of it, though.