First, shipping inside Canada is much more than within the US. It would probably cost near that much to send it from Montreal to Toronto (2 big cities not that far)
Second, well the population is much less dense in Canada than in the US. We have a few "big" cities, but otherwise the population is less dense for quite a big territory. And some laws state that the shipping cost is to be the same in all the country (I think), so basically we pay more to be able to send something far far away. Add many other factors and in the end we pay a lot more for everything.
So yea, I suspect that many Canadians "cry" when they see the price of something in the US and the price in Canada. In fact, I bought a few things recently from amazon or ebay and it was MUCH cheaper to order it from the US, pay the shipping, than to buy it from the Canada.
And I don't want to start anything here, but the American government is one of the most protective around the Globe, so these "free trades" are bull**** and only applies when they want it to. Look at the wood industry for exemple ... I don't say that they should not apply rules to protect your jobs, but don't pretend that you apply these "fair trades" (or whatever it's name) after that.