Got to find it amusing that it takes in-depth research to prove the bleedingly obvious, and quite surprising that it triggered debate IMO
People rarely (if ever) get rich by being fair, honest and following the law to the letter. They get rich by being "go-getters" and not letting anything stand in the way.
It's all in getting away with it. The more someone can get away with trampling on people, breaking laws / morality etc without repercussions ("getting away with it" includes internal sense of guilt/remorse), by nature, the further they will succeed in getting what they want while others who get away with it less hold back.
You could go right the way back to cave men. The one who knocks everyone out and has the meat to himself isn't *nice*, but he's still the one who didn't go hungry.