Uh...yes. It is. It's not going to spike up a ton, because it's simply not easily available everywhere.
Do you have any proof of that, or anything to back up your point, or are you indeed just clutching at straws?
You see, I was in my local Bik Camera this morning, and there were plenty of Wiis there just waiting to be sold.
The fact of the matter is that Mario Galaxy didn't shift much Wii hardware, and that Wii hardware is not in short supply in Japan.
PSN - hanafuda