It should also be emphasized that they're certainly cruel because if they're just powerful, there would certainly still be a lot of people who would voice their dissatisfactions and rally all those around them.
But if they're also very cruel aside from being powerful, then those people that they were treating as slaves were probably too afraid to resist, and afterwards, most of them probably just got used to it.
Of course, some of them were probably still very uncomfortable with the current way they were living, but instead of resisting, they just found a way to escape.
Well, they were also people who obviously didn't have enough strength and also feared those people, so it's also good that they just thought of escaping rather than confronting the others, as they would probably just die without even being able to do anything.
