As you can see of the 250 games on this one only a handful is really commercial, those that you can download anyway.
The compilations in question are pirate ones with full commercial games, not just a few; all of them. Those are the compilations sold by hmv, etc, and always can be traced back to the same bastard, no matter what his company is called at the moment or which of his dozens of websites is active.
Rest assured apart from this pd collection the ones being sold are all illegal, including the mame, zx, atari, neogeo, nintendo, sega who knows what else "legal collections".
Also pc2amiga is being sold by them as their product, renamed to amiga2pc or something equally innovative.