In Los Angeles last Thursday, employees of Walmart participated in a sit-down to demand a wage increase to $15 an hour. Walmart has yet to react in a positive way to this strike but sit-downs have been successful in the past. Back in the 1930s there was a large retail store similar to Walmart called Woolworth; employees conducted numerous sit-downs that eventually lead to wage increases.
See "Sit-Down Strike at Walmart and Win? Its Been Done", Dana Frank, The Huffington Post, November 19, 2014