We do almost all of our food preparation outside, except in the worst of weather. We use an electric griddle and an electric skillet for almost everything we fix. Our Outback has a flip down 2 burner stove and outside hot and cold faucet with a no drain sink. We use the flip down for water, especially washing dishes, but rarely use the 2 burner propane stove top. Almost everything we do is on a picnic table. About outside refrigerators? We have an electric cooler, on its back its a cooler, on its end, it's a refrigerator. When we need extra refrigerator space, we use this. But there again, most of our camping, we never need it.
The flip down stove top is OK for boiling water (which the electric griddles can't do), but that's about all we've used them for.
We've done a lot of camping, and we people watch. (when you get older, you just do this). And one thing we've noticed about outside kitchens, folks open them up and use the refrigerator for drinks, and that's about all. It's amazing how many folks will have the outside kitchens and then still do food preparation over a camp fire.