And, the Empire only destroyed 1 planet in response to the rebel attacks. The rebels destroyed two death stars. Chances are, the rebels killed more people than the Empire because a planet can only really be populated on the outside surface of the planet but the death stars housed their entire staff 3 dimensionaly throughout the whole structure and could probably hold way more people than you would think. Not only that, most of the people working on the death stars were simple contractors. We only saw the military in the movies, but the military was only a small percentage of the population on the death stars as they did none of the construction. The construction crew population on the death stars must have been 10 000 to 1 or something like that given the vast amounts of technology and mass required. Plus, the empire did not have their entire fleet INSIDE the death star. Their fleets were deployed all over the galaxy and based on the movies, virtually none of the fleet was harmed as a whole. So, the rebellion really didn't do jack shit to the Empire by destroying the death stars, they just killed a bunch of contractors trying to do get a paycheck to feed their families. // EDIT: Great point about the ewoks, never thought about that!