Not many cops are out at night, you can’t get the killer drivers with the .20 & .30 if all of the patrolmen are at the station drinking coffee, staying out of the cold and booking .05 sober people.
I guess you’ve never been stopped at a road block before?
I have never understood, assuming they really want to cut down on drunk drivers, why they don’t station themselves outside of every college bar parking lot in sight.