I’ll admit this is an autistic pet peeve of mine every time someone says “you can’t play *delisted game* anymore!” No, the publisher did not hold a gun to your head and force you to not play the game you already downloaded to your hard drive. For that matter, they didn’t take away your Wii/Wii U/3DS purchases, you can still download anything you already bought (actually I’m not sure about Wii anymore, but you definitely can for those other two).
This, on the other hand, is a literal example. There’s no reason they couldn’t have just added some kind of offline mode, even if it’s just for the single player part.