Reminds me of another time & place... I was crossing the border between North Dakota and Manitoba once back in the early '80s, and Canada Immigration and Customs manned the guard shack on the northbound side of the road, with US Customs and Immigration agents over on the southbound side. I was somewhat taken aback because there was absolutely no barrier of any kind on the road at the border (and prior to that crossing, I had only been up to Canada via either the crossing at Niagara or at Windsor/Detroit, where they treated the border with a little more formalism). In fact, while there was a light on in the Canadian guard shack, nobody at first came out to meet me when I stopped my car at the shack. I sat there patiently for about 5 minutes, and then decided to go look in because I didn't want to drive off only to have someone chasing me down later.
I found the guy in the shack watching TV, and he was clearly a little miffed that I was interrupting his break. But once he realized that I was only trying to do "the right thing" his demeanor changed, he became rather friendly, and he told me that nobody ever stops to check in at that crossing. He also advised that on my way back south if I didn't want to go through the hassle of checking in with the US side (where, frankly, the agents often did full vehicle inspections to relieve their boredom), I should instead cross at the gravel road that I'd passed about a half mile back -- since that road, although no longer maintained, was still passable and was completely open and unsecured. That was where all the locals crossed. He was right; on my way back I found that gravel road and took it back into the US. Nobody noticed.
I have to admit, I miss those days....