Just to irritate myself, I sometimes surf eBay's or Amazon's Canadian websites (I still don't know why the Canadian versions even exist), looking for some product I need.
Most recently, it was a pair of spectacle frames that are expensive, but which, I know from experience, fit my strangely shaped face.
The Amazon.ca sellers that offered them all turned out to be based abroad; you discover that when you type in your Canadian shipping address and watch the delivered price explode.
In the case of eBay, the experience is even more masochistic. Usually, a Canadian eBay seller doesn't have the product you need. EBay then helpfully lists a slew of American sellers who do, some of whom are willing, for a steep price, to pilot your purchase through the Canadian border blockade. Others just refuse to ship to Canada.
It's just one of the prices we pay for remaining a small, quasi-socialist state on a continent where, in general, markets are freer than anywhere in the world.