Advertisers are just a bunch of people paying money to blast our ears and eyes with spam about their products. They're not philantropists. They're not financiers.
Facebook is a vehicle for said spam, disguised as a social network. Yes, it has to offer some value, otherwise no one would stare at the ads.
Putting Facebook and advertising in charge of providing facts and information is a stupefyingly bad idea. It's already shown that it can't provide either.
And if they really want to do it, then they should be regulated.