Broad brushes over such a huge industry on a national basis are stupid. The US produces cheese to the order millions of tons. You can go to any supermarket in America and choose from literally hundreds of varieties of domestically produced cheese...everything from the snobby artisan stuff in the frilly packaging that brags about being "cave aged" to the giant bulk bags of shredded whatever dusted in cellulose. Could be the fast food people in Canada like exploited are only getting exposed to whatever comes below even that...the bulk restaurant supply shredded crap meant to be melted on shitty pizzas or into cafeteria slop.
Of course...this isn't true for most. I'm in Canada quite routinely and the stores stock what to me are local brands, in addition to their own domestic stuff, which is basically the same spectrum of expensive quality to cheap shit.
On the other hand...Budweiser exists, so American beer must suck, right? Transitive property?