The root of my theory is in the yo-yo concept. It seems that things constantly swing from one end of the spectrum to the other. At first there was diversity in stores. There was a separate store for everything. Then came the chain stores. Finally there came the big box all-in-one store. I think it's about time for the pendulum to start swinging back in the other direction. As people give up their cars, they might not mind going back to the old skool style of shopping. You buy your bread at a bakery, your meat at a butcher, and your veggies from a produce market. These store would specialize in a particular commodity so they could devote themselves so much more to quality and variety. I envision a place like the current "Furniture Row" concept where there are a few stores stuck together with a particular focus, but they are separate stores. I guess I am envisioning a mini-mall grocery store where you can buy each set of items separately. Why? Because perhaps you only need a particular item. Each store would be run independently so each store could devote all of their effort towards the items they carry. It sounds like more work than what it's worth, but it's essentially an update the old concept of specialty stores.
I guess another thing that spurred this on was that I saw cell phones for sale in a grocery store. To me, that's taking the whole one-stop-shopping thing to the extreme or the absurd. Perhaps my idea would be even more well received if we ever get into a situation where electricity becomes insanely expensive as well. We will all get rid of huge freezers and go to small refrigerators with just enough room for a few meals. We'll all be buying tonight's dinner tonight!