Remember also, Nintendo or other companies could always release patches. There's been something on Nintendo.com (luckily I still had my username from about 8 years ago) that lets you update your games with special things only if you've registered your Wii and that game. In the Wii shop channel, there's the option to connect your Wii to your Nintendo.com username, the reason for that is because of this I'd assume.
Lemme give you a quote from Nintendo.com:
Here's the exclusive content for this game:
Sorry, special content areas temporarily unavailable.
That's just something to think about.