Speaking as a Canadian hunter with an interest in the products that go along with the sport, these rules are very frustrating. America truly is the "Land of Plenty" when it comes to the retail sector, no matter what industry we are talking about. The buyimg power in the U.S. is simply staggering, when compared to most other countries, Canada included.
To give you an idea of what I mean, my wife was replacing her car this year, and decided on a Nissan Rogue and wanted a specific colour. The sales guy at the delearship was trying to track one down, but missed out on a couple because he was too slow to act, and the cars were "re-routed". When I asked what that meant, he told me that if a dealership in the States wanted the same car, they had priority, and the car was sent there first. When I asked why, he said that the market for new cars in the STATE of California, was larger than the market for new cars in the entire country of Canada.
This buying power allows U.S. retailers to buy in bulk, then pass on the savings to the consumer. So, when I am online and spot a good deal on something as innocuous as a pair of binoculars, or hunting scope, and attempt to purchase it, being denied at the checkout page does not make sense to me. The same products are generally available here, but at a much inflated rate.
It does not seem to me that any "national secrets" are being protected by not shipping a product over an imaginary line on a map. More like the middle man is getting rich by taking advantage of some arbitrary set of sweeping rules that really should not apply in these instances.
P.S. The Leupold VX R 2-7x33 scope I used to shoot the pig in my photo, the one to the left of my little rant here, was bought in Canada, and yes I paid too much for it.