quote IshperYooper: "I am a little confused with the vehicle permits. Do you always need a vehicle permit as well when traveling/camping via canoe in the Quetico? Or do you just need a vehicle permit when camping in the BWCA and taking day trips to the Quetico?"
Vehicle permit = day pass, so you don't need a vehicle permit if you have a rack country camping permit.
As far as cross checking, I think less of a union jurisdiction and more simple job description. Also, I read US rangers were refusing to check border documents because it has gotten some shot at. I don't think the rangers signed up to stop smugglers - I suppose unless smuggling fish or trees maybe.