I am currently in the rural south and have to say you have a VERY valid point. You have to go many miles for an actual grocery store, but can find various discount small box stores as easy as a gas station.
Although, I do remember when I was young [in the last century], visiting for holidays, there were general stores and country markets at an even larger scale.
An odd example of the loss of 'small town business' by replacing it with branded chains.