Perhaps they've seen how well this practice works on a subset of the American population and decided to emulate it because it was their best and least worst idea? While a bad approach it certainly seems to resonate with some portion of the populace.
This is exactly the danger. Morally egregious, but extremely effective advertising for the large swaths of uneducated and ill-informed. What is to stop a private corporation from polluting national discourse? Apparently nothing, now that Facebook has taken the drivers seat spreading loony conspiracy theories. This Russian playbook is public knowledge now, and intimately studied for better or worse.