Because all of the protectionism in Canada is in support of local interests: dairy farmers, brewers, etc. Remove the trade barriers, and the crappy ones will d

Because all of the protectionism in Canada is in support of local interests: dairy farmers, brewers, etc. Remove the trade barriers, and the crappy ones will die. That's a much bigger deal politically than the win from efficient firms doing better and prices going down. The federal government just has no real incentive, short of it actually being in the nation's best interest, to force internal free trade. They would have to expend significant political capital to do so.