Fresh Express is abandoning a $308 million deal to acquire food company Dole’s vegetable business, the Justice Department said. “At a time when food companies are already overcharging Americans for groceries, [the] abandonment preserves lower prices and availability for an essential kitchen staple,” the agency said in a statement Thursday. Advertisement The collapse of the deal with prompted partly by regulators’ concerns that the partnership would reduce the number of competitors from three to two. That would in turn raise grocery prices for items