There is an agreemen
There is an agreement beewetn Canada and the US that SMALL amounts of coinage are accepted at par. Therefore if you get one or two Canadian coins in your change you should be able to spend them in SMALL amounts. If you want to press the point with a merchant the next time you get a Canadian coin in your change just pass it back and say no thanks I want an American coin . It is just businesses that are refusing to take it after all a nickel is a nickel.