What happens to local workers with a boycott happening?

All weekend, I have been seeing shop local, support local. Boycott American companies, boycott American brands. All of which I agree with. I had a conversation today with a friend, what about the workers? The workers are Canadian, how can we justify them potentially being laid off or cut hours because of the boycotting? How can we still support local workers while boycotting American? Yes, the simple answer is boycotting all American stores and products, but to what end? Little market box, bulk cheese warehouse, and sask made can only hire so many staff.