Because you'd probably be scratching your television.
As you can tell by the trailer above (and new screens below), Hudson's localized Blue Oasis (at E3 they announced it for North America under the name My Aquarium) doesn't require a rocket scientist to figure out. Hudson has gone ahead and basically crafted a virtual fish tank, allowing you to enjoy the serene company of aquatic life without having to clean a pump every month.
If you already checked out the tour of the Japanese game, then you know the title is chock full of content. And, if it's priced the same as its Japanese counterpart (500 Wii Points), we won't have to shell out a lot of clams for it. Get it? Hey, where are you going? Hello?