If for face to face play you are expected to have a physical version of your character I think the same should be expected virtually. I don't see how it is any easier to scan a chronicle sheet than it is to print a chronicle sheet (in fact for me it is easier to scan my physical sheets then it is to print my virtual ones) and a player can very easily write out their character sheets in a fallible pdf version for online use. I think GM's should have every right to ask for this information. Perhaps it should even be encouraged for organizational purposes.