On a sunny Friday in August, a vanload of a dozen wide-eyed tourists step onto Main Street in Midway, Kentucky. The picturesque town with a population of fewer than 2,000 is easy to miss passing through, but for travelers who do happen upon it, the charming community is one they'll soon be eager to revisit. "This is just a lovely town," said one woman from Kansas after touring Midway's historic downtown for the first time. "It's amazing how clean the storefronts are and how friendly all the owners are." "There's...