It will happen very soon because people actually don't use cash or checks either for that matter for anything other than a small purchases like a candy bar. All bills that can be paid with Bill Pay or Pay Pal or some other method are already so popular you can't undo them. Income is almost all direct deposit and will soon be required. Cautious people like yourself have already began gathering up silver coins which will work for a while but like Roosevelt removed gold, silver will be removed too.
Don’t know where you are, but 0bama’s gig economy is all around the South. Only folks with 9 to 5s are cashless, gig folks are strictly cash.
Want your house painted, cash. Want your roof fixed, cash. Want your driveway paved, cash,lawn cut, cash, etc., etc. The dealership will fix your car and take electronic payment, Bubba will do it on the weekend for cash at 1/2 the price (his day job is working at the dealership).
Pay by check and the price nearly doubles, EFT payment, nope.