Is there a C64 equivalent of World of Spectrum where the site tries to get permission from the copyright holders to offer the games for download? If so they could just give a link to that site, or they could just include games that they have permission to distribute (maybe they will strike a deal with the copyright holders?)
As long as there is a legal source for the disk/tape images, it's no more a promotion of piracy than Dell selling a gaming PC knowing that some people will play a pirate copy of Crysis 2 on it, IMHO.