the sad fact is that demand in the US market is too high and if you are the distributor, why export it when you can sell it at home. The more folks try to hoard it, the tighter the supply and up goes the price. Canada is a secondary market when it comes to firearms, ammunition and accessories. The small size of our actual market makes it more expensive for companies to export gun parts, add the legislation component and we cant get much of what we desire up here unless we choose to pursue through a dedicated broker etc.
It isn't the local market setting the high price on the ammo, the dealers are paying inflated prices as well, we as the consumer are stuck, either you want it or not and you pay what they ask or you don't get it.