A locally owned grocery in Pleasantville, Iowa. Photo: Ashton B Crew, wikimedia commonsA few weeks ago, when the Obama administration released its Food Desert Locator, many of us realized that a once-good idea has spoiled like a bag of old bread. If you go online and find that your family lives in a food desert, don't worry: You have plenty of company. One of every 10 census tracts in the lower 48 has been awarded that status. Two years ago, when one of us (Gary) moved to the village of Patagonia, Ariz., he inadvertently chose to reside in what the …