Reading the item description reveals that this is not actually the game, but rather a code you can enter in the Wii Shop to get the game (Presumably, you have to enter it instead of a Wii Points Card code). This seems to be a reaction to Microsoft - they recently started putting codes for Xbox Live Arcade games up for sale.
Although this will be pretty useless to anybody who frequently buys games from the Wii Shop it could be invaluable to someone who has almost no interest in any games - If World of Goo is the only WiiWare game you would like to have you can simply buy a code for it alone and enter it on the Wii Shop. Of course, you'll still need an internet connection to access the Wii Shop!
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