Never mind that, the major issue is real estate: a horizontal fridge uses twice the real estate, and in a Western country the cost of that small patch of ground will vastly exceed the running costs of the fridge.
- Put the fridge under a counter on rollers (with a cableway for the necessary electrical hookup).
- Put rolling shelves(with lips) inside the fridge to allow ready access to the bottom storage areas.
Even if consumers won't trade off a little bit of convenience for energy efficiency today, they probably will when electricity is much more expensive.
I'm inclined to think that engineering improvements to a vertical fridge is easier than the changes required for a chest fridge.