I believe what you are saying but that is odd. They charge you a duty to drive it across the border but not ship it across the border. Is it the same going into Canada? I have known guys to have their saws and parts sent to a US address that they can go and pick them up from then drive in Canada. I just assumed that was to avoid duties.You will pay duty coming back unto the US. US Border Patrol collects.
Also I wonder how it works when all the semi loads of hogs come from Canada to the US. That was killing the US hog market years back. This duty crap is ridiculous. What hell was NAFTA supposed to fix