If they're shipping to the territories, yeah. I imagine they do charge at least $500 extra for shipping if they ship there at all. A jar of Cheez Wiz costs $23 USD/$30 CAD in Iqaluit because of the shipping expense. But the rest of Canada is just as accessible as the northern U.S.
Here is a population map of Canada. 90% of the population lives within 160 km (100 miles) of the Canada-U.S. border. The black areas on the map, the "sparsely populated" zones are almost entirely untouched wilderness with no roads, no railways, no human settlement of any kind. It's an endless uninhabited expanse, most of which has probably never been seen by human eyes. There are a few seasonal ice roads that trucks can take into some of the black "sparsely populated" expanse that lead to tiny First Nations communities like Attawapiskat.
The only way to travel to Nunavut is by plane — there are no roads that go there. Food and other cargo is sent to Iqaluit annually by ship. You can drive to the Yukon and the Northwest Territories. I think it's the same route you would take to drive to Alaska.
Contrast this with a population map of the U.S. The entire contiguous U.S. is inhabited.