Comment by bluGill

> Definitely not a win for consumers, who in aggregate lose out. The margins to make the system work are built into the prices you pay at the checkout.

While not wrong don't forget that cash also has costs that are built into the system - there are a number of theft ways to lose money with cash that don't apply to cards. Even when everyone is honest there is the time cost to count all that cash. Somewhere between the two is mistakes in counting.