[Dai]

I don't think it's as simple as lack of caring alone. In America and this country we now have a legal system that penalises people for trying to help.
If someone had moved that man out of the road or even lifted his head to put a pillow underneath there would be a queue of lawyers waiting to sue you for aggravating his injuries.
Until such time as we are safe from such malicious prosecutions I'm not sure that I would dare offer help either.