"Dad, can I have my allowance?" "Sure, let me just find my phone....ok, firing up my MobilPay app...selecting your name from my contacts....entering amount of

"Dad, can I have my allowance?" "Sure, let me just find my phone....ok, firing up my MobilPay app...selecting your name from my contacts....entering amount of $10....entering my PIN for confirmation.....whoops. Getting an error. Let me try again. Uh oh, looks like the service is down at the moment. Sorry, son...you'll have to wait. Maybe it will be back up in an hour or so." (If you don't have kids, substitute with a yard sale/flea market, handout to a panhandler, impromptu purchase at a food truck, repayment of a small loan to a friend, etc...) Mountain of privacy horrors aside, a cashless society still looks like hell if you need to engage in a transaction with anybody or anything that doesn't have a card reader. And the solution is neither "don't have those transactions" nor "add more card readers".