^This.
When I lived in Pennsylvania, driving slower wasn't a problem. There was a town every few miles where I could buy what I needed. Out here in Nevada, going to "town" means Reno, 175 miles away...and other than fuel there is NOTHING you'll be able to buy in between. "Town" heading east is Salt Lake City - 360 miles. "Town" heading north is Boise, Idaho 250 miles. And "Town" heading south is Las Vegas - 500 miles.
So I ain't gonna drive 65 when I can drive 85. Especially when the roads are long and straight and you can see 15 miles ahead. Don't need extra hours sitting in my rig!