It's my experience that those who "drive for their jobs" are often some of the worst drivers out there, especially American police officers who for some inexplicable reason think they have priority whenever they are on the road!
18 wheelers are the most dangerous and it's been studied that they are some of the most sleep deprived workers. I think I read it's like 3-4 thousand deaths a year.
Even with rules, regulations, companies will still push workers to get more done and on the quickest timeframe.