Sure, it would be pretty easy to smuggle small, high-value items, but most of the trade volume is in large items like lumber, steel/aluminum, new vehicles, and potash, and it's pretty hard to sneak a dozen 18-wheelers across the border a day. Electricity and oil are also pretty common exports, but those are even harder to smuggle since they go across in fixed wires/pipelines.
Sure, it would be pretty easy to smuggle small, high-value items, but most of the trade volume is in large items like lumber, steel/aluminum, new vehicles, and potash, and it's pretty hard to sneak a dozen 18-wheelers across the border a day. Electricity and oil are also pretty common exports, but those are even harder to smuggle since they go across in fixed wires/pipelines.