Fear.

They got everything they could ever want served to them on a silver platter, purely because of their sex. No effort, or at least, no REAL effort that merits such results. But because there was no effort, there is no security.

So they need to create that security. 1) Ensure no one can accuse them of wrongdoing, even if they're doing wrongs. 2) Stop other women from succeeding in the same way with the same person, since it would oust their comfy position. 3) Increase their relative value to the commoner by completely crushing the commoners, so that even if they fall, they would need to fall VERY far indeed to actually fall to the level of a commoner.

Doing these three things requires organized movements, and lots of power used very unethically.