Maybe a runaway? I know that log books aren't being used and drivers are being pushed to deliver as many loads as they can. Maybe he or she is exhausted and should've pulled off the road to rest. Of course they could just be an idiot too.
Could very well be plain old exhaustion. I was reading a story online earlier today about how hard they're working and not enough drivers for the loads.
(But you could be right and they are just a knucklehead too)