This is why just about every WiiU and/or 3DS owner changes their location to a tax-free zip code.
Haven't thought of that.
Though I don't see why your complaining. This is how the world works! You buy something, it has taxes. The eShop cards to cover it, though you just have to keep in minds of taxes, no where on the card it says "will pay for 20$ game" and it tells you there is taxes.