Ok, let's put it this way..
Nintendo has a game and they know that it is going to be great hit. They don't want to price it low because people will buy it anyway.
Still they need to add a carrot with a game to convince consumers to buy the game. At this case the carrot is a piece of plastic, propably worth 1 $ + manufacturing expences. With Wii Whiil I would say that Nintedo makes themselves like 20 - 30 $ extra cash per sold game.
Maybe I don't have permission to whine about that because I am one of those persons who will buy the game anyway.
Mario Kart for wii will be a great game and it is also great that they have added online gaming aswell. Can't wait for it.