Are you sure they are sold out as opposed to just not selling it? My local Game hasn't stocked any new wii U games since MH3. And supermarkets sell the sme 5 launch titles they have since the system launched.
I'm having the same problem in multiple shops where I live (Portugal). Most stores are selling launch titles only, with outdated (and inconsistent) prices. There's no where I can find Lego City, for example, and nowhere I can pre-order Pikmin 3, Wonderful 101 or Wind Waker HD. And to top it all, Nintendo doesn't sell eShop cards in my country either.
So my only options are either asking for my mom's credit card, as I only own a debit card, to buy on the eShop or order things online.