I was once on the SE Expressway in Boston during a lunar eclipse (a rather common occurrence). Cars slowing down, people pulling over and getting out of the car, etc. It was a nightmare.
Of course, a lunar eclipse is observable from anywhere, so what you had there was just a response to the moment by whoever happened to be on the road.
In this case, you’ve got a potential mass migration building to a crescendo. I plan to be part of it! One thing that slays me is this talk of stadiums, etc. . What’s the point of that? Carbondale is the focal point of the hype, so .... avoid Carbondale! The path of totality is 70 miles side and extends all the way across the country. If you’re within twenty miles of the center line, and have a clear sky (!) ... you’re golden.