"Use values must never be looked upon as the real aim of the capitalist; neither must the profit on any single transaction. The restless never-ending process of profit-making alone is what [the capitalist] aims at... [the] boundless greed after riches".
So wrote Marx, and he was right.
All of us, every day, buy and consume lots of stuff produced and marketed by vicious capitalist corporations. Without it we would starve.
Electronic computers and the Internet owe their development largely to imperialist military machines. We can still use them.
We can put Facebook to good use, too. But, as with every capitalist enterprise, for the capitalists, the social utility of their product is a side-issue. What matters for them is the extraction of surplus-value.
In the case of Facebook, its "good sides" could better be provided by a public service, rather than by a capitalist enterprise geared to maximising advertising revenue.
PS: a useful review article by Stephen Burt on this and related issues:
click here. "None of the people who developed Facebook expected to bring those changes [good and bad, in facility of communication] about: they wanted and thought about nothing but money and sex..."