So I only see two major downsides:
 1) I basically I have to verify&#x2F;transact every &quot;printed&quot; money the moment I get it - preferably using a smartphone - in case someone else has a copy of it and &quot;takes&quot; it first. Copies could be made with any high-resolution camera.
 2) If the money travels from A to B to C in paper shape and the digital transaction will be from A to C then A will know that B has done business with C.