[rb2018]

Facebook can just charge 1$ per sign-up and the problem is gone (faking credit cards etc does not scale).

Of course, as others have said, they prefer having more "users".

[dymk]

Are you honestly suggesting that requiring having a credit card is in any way a solution to fake accounts? That's a ridiculous proposition not just for Facebook, but any service that operates in developing areas or serves users under the age of 18.