Nothing to see here, no questions to answer
Facebook's code, Facebook's service, Facebook's service. The mugs (i.e. users) gave Facebook an irrevocable, royalty free, global license to use everything they handed over for any purpose whatsoever.
That was their choice, they were free to make it. Now that Facebook has done something with their own products, the mugs are crying like little bitches. Well, boo-hoo.
If you don't like it; stop using Facebook! No one is forcing you.
A waste of taxpayer's money.