This is great, Facebook should add "Two Minutes Hate" feature to the user timeline to address the spread of misinformation by these enemies of the people.
Facebook most certainly has not. You can get paid very handsomely for facilitating misinformation that wouldn't otherwise catch on without a lot of surreptitious advocacy, preferably astroturfed. The cash value of this has everything to do with how well you can get away with it. It's just market dynamics in action.
They are simply running into externalities, that's all.