Ban parking charges in motorway rest areas/service stations for stays of under 12 hours so that tired drivers are encouraged to stop and recuperate, for free, before continuing their journey (as is common practice in other developed countries such as France). Tiredness kills, as does profiteering.
You may be interested in these active petitions
From the Royal Society for the Prevention of Accidents:
"...research shows that driver fatigue may be a contributory factor in up to 20% of road accidents, and up to one quarter of fatal and serious accidents.
These types of crashes are about 50% more likely to result in death or serious injury as they tend to be high speed impacts because a driver who has fallen asleep cannot brake or swerve to avoid or reduce the impact."
https://www.rospa.com/Road-Safety/Advice/Drivers/driver-health