Generally people don't drive the speed limit. I remember a university around here took 3 cars and drove the speed limit on the turnpike for 75 miles side by side during rush hour. It basically destroyed traffic patterns that day. Cops don't even enforce the regular speed limits during rush hour on major Highways.
I do. I grew tired of watching for cops. It's much more relaxing to just set the cruise control at the speed limit (+/- 1mph).