I don't think this "subscription service" is actually for the user I think it's for the advertisers. I think the fee is just a smokescreen. I imagine FB having access to something like a driver license gives them your address, height, eye color, signature, data of birth etc. I'm sure they will monetize this in all kinda of new ways. For example maybe political adds since you can target based on voter precinct, auto insurance, neighborhood demographics and of course a premium tier of "blue checkmark verified" eyeballs to advertisers.