The Virtual Console was one of Nintendo's smartest decisions, both financially and consumer-wise, in a long time.
And yes, it's definitely needed. I feel like it could've been used on the DSi at least. The DSi could definitely handle Gameboy/Gameboy Color games at least, possibly even the GBA. Not to mention the potentials of the Neo Geo Pocket, Wonderswan, Lynx, etc.
While it may be just "selling emulators and ROMs", it's also a great opportunity to bring games overseas. They brought Sin and Punishment to the USA via Virtual Console, and it was successful enough to spawn a sequel. In both Japan and other regions. Imagine bringing official localizations for games like Mother 3 (the fan translation is great, but it's still a fan translation).