What keeps people in line in a capitalist society is everybody has something to lose. Oh wait, what about poor people? That's what prisons and churches are for.
Good thing the poor still believe in the Ten Commandments, otherwise the suburbs would burn like a pile of tires. The only thing that keeps Bill Gates rich is a security fence and the hope that maybe there's an existence beyond this one where 2,000 people don't own most of everything.
And if churches and prison don't work, there's always ignorance. American kids get the worst education in the civilized world. And thank God. 'Cos if we give poor kids an education, they might start asking dangerous questions, like "Why not tax the rich?" or "Why can't poor kids with straight A's go to college for free?" That's treason. How dare we betray our values with equal opportunity? It's unfair to rich people.