Someone's still holding the rights to these cartoons, jus because they are not for sale anymore, doesn't mean we can download them at free will. It is still illegal anyway you look at it.
It's same with games. 3 skulls of toltecs is nice example, the game is impossible to find, but developers still don't offer it as freeware on their site, do they? If you download it, you're breaking the law, simple. Does anybody really care? Probably not