Wal-Mart shuts down a store in Canada rather than give in to union demands. Note that the store's employees had already been granted union status. Trouble began when the union demanded that the store hire more workers. There are workers who really needed their store jobs, who abstained from union votes and now face unemployment because some of their co-workers insisted on making a point.
Many see these union efforts in Canadian Wal-Marts as the first step in a grand plan to unionize Wal-Mart's USA employees. I wouldn't bet on that happening. How effective are the unions here at getting anyone elected to political office? Not very. Unions are a mixed bag, image-wise.
And given the choice between low prices or a union presence, it seems Americans have already expressed a preference.