I live just 22 miles from the center of Houston and all calls to Houston are long distance. Even the next town, only 5 miles away is long distance.
The opposite is also true. There are some rural parts of the country where an area code covers an enormous region, and many calls within that area code can be "long distance" if they are made to points that are far away.
Long distance? It's just a money making scheme. With everything so computerized these days, it doesn't really cost them extra.