Researchers regularly make use of work from other countries, the scientific community is international. Even if one could make an argument for not allowing Canadians to access US research without payment, it doesn't follow that Elsevier and friends are the ones who should be paid.

Research done by government employees is legally required to be public domain. I see no reason we shouldn't extend that to researchers who take government funding.

I'm in the U.S. and enjoy a few Canada-based journals that detail work funded by Canada. Fair trade, eh?

Sure. Same way that if you were to drive down for a weekend and not pay taxes on the roads you specifically used across the border.

Until thousands of Canadians come down every weekend just so they can use American roads and then go back home to fill up on gas, we won't worry about it.