Now, game retailers aren't doing it for charity. The profit on one unit of Wii Fit isn't going to be much different from the profit on one unit of, say, Mario Galaxy. Now, given the choice between selling 20 copies of Mario Galaxy, and 1 unit of Wii Fit, which do you think they are going to opt for?
Obviously Wii Fit, because your other thread is suggesting that Mario Galaxy doesn't sell well anyway.
hanafuda may have not many posts, but the threads he starts are usually entertaining when looking back at them a few weeks/months later.