That's a great idea until you see the "international" shipping rates!!!

It makes everything pretty cost-prohibitive. I do carry the odd seasoning packet or whatever back for my sister and my mom is pretty good about sending a big box of chocolate and Hickory Sticks for holidays, but otherwise I need to go years between shipments of the heavier items. There is a site online that will ship certain Canadian foods within the U.S., but they use UPS ground and it costs about $20 to ship a box that is under 10 pounds. I haven't been that desperate yet. It wasn't that bad when we lived in Oregon and drove up to see family a couple of times a year, but the trip we took this past weekend is the first time I have driven to Canada in the last 13 years!
As for "all the cool foods we don't have," yeah...I was amazed at what you don't have. As an example, in the U.S., we have an entire grocery aisle devoted to flavoured but unsweetened seltzer waters. We drink a lot of it and had packed a bunch for our trip north, but wanted some for the return trip. I was able to find ONE flavour, in a case of cans, in Lablaws. I felt sad for you guys at that point. But, on the bright side, you do have poutine in a can! (My kids made up a song about it after they spotted it. They were so disappointed that we couldn't bring "animal products" back across the border with us.)