Our findings suggest that if the pursuit of self-interest goes unchecked, it may result in a vicious cycle: self-interest leads people to behave unethically, which raises their status, which leads to more unethical behavior and inequality.
Paul Piff, quoted from Shame on the Rich [sciencemag.org] about research into ‘whether dishonesty varies with social class’
For my own experience, I can state that, without doubt, people in Singapore who drive expensive cars (one of the things studied in the research), drive like they own the road. I remember this was the case in the US too, but in Singapore when we talk about expensive cars we are talking about 50% of the cars on the road (BMW, ‘Benz, or more expensive!). That many asshole drivers makes the traffic in the tiny island of 5 million, with very good infrastructure, as bad as the traffic in New York City with it’s much larger population!