It is certainly understandable to be unhappy about having to pay the shipping. Especially since you probably had the issue right out of the box. If it was more into the warranty period (like say 6 months) I would consider that more understandable. I guess if that's their policy that's the way it is.
I will say from experience that shipping into Canada is very expensive. I am in the auto parts business and anything heavy going to Canada can cost many times what it would cost to ship in the US.