Yeah, but they only want to stay until they don't want to stay anymore, then it's their God given right to come home and drag the plague with them, which of course, they just assume they don't have.
Or they get sick, and their medical insurance (or lack thereof) isn't going to cover them because they were told to not be there in the first place...then it's a mad panic to get home for our medical system.
Then they want to rush home at their convenience, be damned anything else.
Not failsafe - you can be infected for a few days before you'll test positive, hence the quarantine thing regardless of test results.
A useful tool, sure...but if some Canadian returns home from the Covid cesspool that is Florida right now I'm not putting any faith in a quick test at the border right now as being a failsafe indication they can come mesh with us again...sit for your 14 days and make sure you're not actually sick despite not being sick enough to trigger a positive quiet yet.
the irony is that many of them may miss slots for vaccinations while they are away....imagine if future travel requires vaccinations....what a catch 22.