Local news was discussing how things are tightening up at the bridges (US - Canada border). Things like increased scrutiny coming AND going, slower crossing times, biometric controls... we like cross-border traffic here, it's an important part of the economy. Slow things down, and people just won't choose to visit because it's too inconvenient.
Then there's all the students and faculty at local colleges and universities affected by the travel ban. DS4's classes just resumed today, so not everyone may have made it back in time - if you had a semester break of more than 5 weeks, wouldn't you travel home for the holidays? Especially when you are expected to leave the dorms, and meal service doesn't resume until 1/29. If home is too far away, might you take the opportunity to travel to Canada between semesters? The news mentioned the economic effect here - universities encourage foreign students, since they pay up to 3.3 times what locals pay. Scare them away, and the schools are underfunded.