I remember when this happened. Some guy tried it in Houston and it lasted about 10 minutes before he stopped that nonsense. Can’t you just imagine some of these fast food cashiers trying to figure out the exchange and conversion rate? They can’t even do it with dollars for dollars with their electronic computer.
I had a friend who worked at a bank in college. He deliberately requested a stack of two dollar bills and then took everyone to a fast food place to order off the dollar menu. Utter confusion, with threats to arrest him for trying to use counterfeit money. None of the clerks or even the manager had seen a two dollar bill.
That type of confusion or the ability to pass fakes only goes up with other currencies.