Of course they don't exist in the same way. This is 2013. What you're describing is some sort of semi-mythical pre-WWII world.
Technology changes everything. TV killed small movie theaters. Netflix, etc. killed video rental stores. Amazon killed brick-and-mortar bookstores. Ubiquitous cars killed passenger trains, and meant putting the big shops on the outskirts of town made more sense than putting them in a smaller building right in the middle of downtown.
And guess what? If you live in a small, rural town, pretty much all those changes were huge net positives. (Presuming, of course, that you have a car, a TV, and Internet access.) Sure, you don't have a local theater anymore. But the local theater was the only way you could watch a moving picture of any sort back then. Now you've got 200 channels of TV and cheap streaming movies on a big screen right in your living room. That supermarket you disdain probably has 5x as many products as the old grocery store downtown did, including entire categories of food they probably never dreamed of carrying, and better prices to boot.
All that said, most of the small towns I'm familiar with have a grocery store within city limits -- and they're small enough places that means they are walkable, at least in the summertime. Indeed, every place I've lived since leaving my childhood home has had a grocery store within walking distance, even though I never even vaguely considered that a factor when considering apartments or houses.
And technology has little to do with this change. Plenty of places are still trying to run bus services. Because ubiquitous cars still aren't. But all the intervening challenges have made that near impossible to do (cost)effectively.
Similarly the theatre is gone because once zoning presses you into a car to get there, what's the real difference between 5 minutes to the local downtown or 15 minutes to the multiplex at the mall?
The root cause was largely a socio-political failure. Self-segregation, myopic zoning, a belief in perpetual growth all abetted by enough wealth on the part of the builders to not care about long term efficiency.