Canada's two-margarine policy is just fine with the Supreme Court of Canada. On March 17, 2005, Canada's highest court ruled that Quebec regulations forcing margarine producers to make their margarine colourless [white] are reasonable.
Unless Quebec changes its rules in the future, the province will remain the only jurisdiction in North America to regulate the colour of margarine.
The intention of the law is, I am sure, to protect the butter industry. And frankly, I wish we had the same law here. But I do pity the poor folks from the provinces who travel to Quebec to find that if they want yellow they have to eat butter. What a let down that must be.
CBC News Indepth: Food