WASHINGTON, D.C., 2016-Oct-23 — /EPR Retail News/ — REI, the national outdoor co-op, opens its fifth flagship store today (10.21.2016) in Washington, D.C. REI has been running 100 days of outdoor events this summer in D.C. under the banner “United Outside” to bring people across the political spectrum together. The effort culminates this weekend with a…