@DKII - I wonder if that is the case. It does make sense.
Though businesswise, if you're taking a $30 cut on the DS (which by all accounts sell well anyway) - you should be making at least the additional $30 on the Wii or other games.
Otherwise you're just giving it away, without any tangible benefit - since the Wii will sell out no matter what. If they are getting more systems than other retailers - it would make sense if the expected marginal profit on those systems (ie average purchase if you include games) is more than the $30 discount they are offering.
Eg. Wii ($30 profit + $10 profit on a game purchase).