Inequality really is bad for society
But not how you'd think.
http://peterturchin.com/cliodynamica/appeal-american-elites-one/
A little theory called "Elite overproduction" essentially claims that when too many people "make good", and you have a glut of rich assholes, that they'll use every dirty trick in the book to make sure they become top dog over their rich ******* peers.
This results in, say, bullshit propaganda mud smears from Fox News and CNN, both owned by rich assholes with axes to grind against other rich assholes.
At its worst, you could end up in a civil war situation, with armies of angry Joe averages and "wanna be elite's" whipped into a frenzy against political rivals.
I like the theory, because I'm familiar with some Roman history, and how really bad things happened when, for example, a Roman general was motivated by his wife to murder a caesar friend who was becoming too big for his britch's. When it turned out the General couldn't realize his ambitions even after killing his friend, he sat and ate dinner as Rome was sacked and looted.
The article is worth reading.