My housekeeper and shopkeeper

She runs errands to the corner store, an intermediary.  I sign the order. and pay the tab every couple of weeks. My ATM charges for cash drop way down, in its place is spiral notebook, ink and paper block chain. I cheat, I know the goods flow the shopkeeper deals with, and I have sub selected my regular purchases for low volatility, we both go through the order book, together, like collusion.  My daily order almost always  the same subset. I have beaten Bezos at his own game, and always will.