ALEXANDRIA, VA, 2016-Oct-19 — /EPR Retail News/ — The U.S. convenience store industry cumulatively invested more than $6 billion in upgrading stores in communities across the country in 2015, according to industry metrics announced today (10/18/2016) by the National Association of Convenience Stores (NACS). The average cost of a store remodel in 2015 was $409,582, up 40%…