I know it doesn't seem right, but it's the developers fault... I wouldn't mind if it the program wasn't an emulator, but clearly the emulator they are selling have derivative works.
Maybe someone should port one of the existing open source emulators like SNES9X to the iPhone/Android.
Yeah, if the program was completely original, then I wouldn't mind them selling it either. Heck, they could probably even get it into the iTunes store if that were the case. But selling something you don't own, it's just wrong... I know they put effort into making this program, but if you're going to make homebrew that supports illegal activity, just don't do it. It's the tradeoff of the homebrew world.