You've just got a different definition of self-interest. :)
Having the plebes cared for so they don't put you up against the wall and shoot you when the revolution comes is, while more long-term, definitely in your own self-interest.
"Here at Ortillery Command we have at our disposal hundred megawatt laser beams, mach 20 titanium rods and guided thermonuclear bombs. Some people say we think that we're God. We're not God. We just borrowed his 'SMITE' button for our fire control system."