Thanks for the detailed reply.
I'm sure this has been discussed to death, but if what you said (bolded) is true, what are some of the best hypotheses of what the actual pattern of Wii customer behavior is?
It goes without saying that many people who buy Wiis do so knowing that Nintendo themselves publishes high quality first-party content (somewhat subconsciously, I suspect?) so there's obviously a bit of a brand-name association factor ("Wii" Sports, "Wii" Fit, etc), and presumably many of these gamers are content playing solely those first-party products (such as myself), or buy an additional console.
Then of course there's an advertising factor. Surely the majority of people who own PS3s and 360s seek out gaming information, whereas the majority of Wii owners are more passive.
There must be other patterns though. I just don't understand why it appears Wii owners supposedly buy so much shovelware. (Do they?) Are they less skeptical that a random game sitting on the shelves might be lower quality? Then why aren't the higher quality higher profile games bought as much? (Or are they?)
Is a game's front cover a huge factor? For what it's worth, I know if I
had to choose, I would pick up a colorful mini-game/party game collection over a darker, epic FPS, purely because I fear a barrier of entry and a steep learning curve with the latter, and the dark deathly vibe interests me none. (Though I say this knowing that I would basically never buy either.)
Anyway, I say all this as a preface to a question about whether it's possible (or probable) for third-party developers to develop a game
like New Super Mario Bros. Wii, for instance (or any game really that appeals to new gamers with its cheerful style as much as hardcore gamers with its nostalgia and intense platforming content; and has little to no barrier of entry), market it similarly, advertise it just as much, and have it sell as much? And would whether it had an existing IP or not really make that much of a difference (Mario being the main exception, I guess)?
I just feel like there's a giant gap in the Wii's market for really high quality, cheerful family games (with newgamer-hardcore crossover appeal), and I can't understand why some third party developers aren't trying even HARDER to perfect a way of meeting this 'need' but I don't really know how to put that into words, and I fear it's just my anecdotal/personal irrelevance speaking.