Banks pretty much can. The only real limit on bank money is the banks ability to find a credit worthy borrower. There's far more of that in the system than cent

Banks pretty much can. The only real limit on bank money is the banks ability to find a credit worthy borrower. There's far more of that in the system than central bank money. Of course the issued currency is balanced with a liability. In the case of normal banks this liability is generally taken by a person or entity in the system. For the central bank it's marked up as not-yet-taxed-away money. Crypto currencies are just silly and absolutely rely ultimately on social stability, which essentially means the state.