I have noticed myself that the most aggressive and dangerous drivers on the QEW are consistently those behind the wheels of high-end luxury cars. 

These people lack empathy for others because they feel they don't need the assistance of anyone else in society to thrive: far too many of these types are big supporters of the ideas of Ayn Rand and of the economic theories of Milton Friedman. 

I firmly believe that many wealthy executives are psychopaths. -Read a book like Snakes In Suits: When Psychopaths Go To Work, and marvel, or shudder, at how closely the attitudes, values, and behaviours of successful executives fall in line with the major defining characteristics of psychopaths, as defined in the Diagnostic Manual Of Mental Disorders. 

These people lack empathy, or as Rush Limbaugh put it more than a decade ago, suffer from "compassion fatigue", because they genuinely do not care about anyone but themselves.