The problem with this is that it isn't as flexible as a normal frige, it basically has to be built into the house. Also, if you don't have it next to a exterior wall, you have to pipe the coolant through the walls or floors. It's a great idea, but it requires a major redesign of the refrigerator, and means you can't easily get a new one if it breaks or you want it bigger or smaller.
Yep, it's not easy, but this problem is already solved with split ACs. While they do require drilling the wall, some people still prefer them to the in-window units.
