Facebook cares about you ...
No, they are doing this scheme to make money.
Facebook are a successful exploitive parasite encouraging people to be foolish and making money by exploiting them. The only difference with Twitter is it's not doing it well enough to make money. Google, even though Google Plus isn't doing well, is the most successful exploitive parasite due to their dominance on Search feeding dominance in Advertising.
None of these companies care about you, except as resource to be milked.