In the case of refrigerators, there doesn't need to be any trade-off between efficiency and heavy duty. The main thing determining efficiency is primarily where the heat exchanger is positioned (top mounted is the most efficient, but uncommon), and the thickness and quality (R value) of the insulation.

If you add extra insulation to an old heavy duty fridge, it increases its efficiency by 50% or more (depending on the thickness of insulation).

The extra insulation, as a side effect of better efficiency through better temperature retention, will also extend the lifespan of the compressor, which will need to run half as much as normal.

The main reason this isn't done from the factory is cost, and to reduce the physical dimensions of the fridge.