While Wall Street rewards big-box stores for their monster sales volumes during the pandemic — propelling retail stocks such as Target to a record high this week — thousands of the country’s small businesses are still hanging on by a thread. The widening gap between retail giants and smaller, locally run stores is underscoring the pandemic’s effect of driving a wedge between the haves and have-nots across the industry, as consumers shift to bulk-buying and one-stop shops. … Sales at small businesses stand at negative 28 percent, down nine points from May when it was at net negative 19 percent, he said.