I could see how communities with say only 30 people along the border go heavily Trump as in those most likely people living there are all CBP and Border Patrol officers and their families and likely not originally from there. I imagine most CBP and Border patrol officers voted for Trump. However I would think places that rely a lot on cross border shopping would be more connected. In Hyder, Alaska, its only 80 people and with no general grocery store, most go across border for shopping. In fact most have friends on Canadian side so very connected. Same with Derby Line, Vermont and many communities in New England bordering Canada. Bellingham, Washington despite being 30 miles south has its economy based on Canadian shoppers and it voted heavily for Biden although also has a university so could be partially that.
Point Roberts, Washington for example is semi-rural and very white and relies a lot on Canadian tourists and it voted for Biden by almost 50 points.
Hyder has no border control, so that's not a reason for them.
