Did they advertise the game? I sure didn't see a commercial for the game.
If they didn't then they can't whine about it. EVERY third party whines about games on the Wii not selling. But it always seems to come back to them trying EVERYTHING except advertising. And the games that DO advertise sell in the millions. It just turns out that the only ones that do are junk like 'Carnival Games' and 'My Sims Agents'.
Stop blaming the Wii and open your wallets to some marketing. You'll do it for your multi-million dollar HD games which probably don't even need extra hype, so why not these games which you call 'lacking'?