Your software retains its value because you still have the physical items to sell - i.e. box, disks, documentation.
If the software was not available on the Internet I don't think anyone would be paying any more for it.
Quite the contrary, if emulation was not around I think you'd find interest in the Amiga would all but have died off by now (and affected the prices you would get for your software accordingly).
Something really annoys me about those who want to artifically limit supply for their own benefit. This goes for hardware and software (kickstart ROMs being a good example) - and it has been a destructive force in the amiga community IMO.
