[Fjolsvith]

FB is a publisher because they don't allow everyone on their platform.

Edit:

We try to make Facebook broadly available to everyone, but you cannot use Facebook if:

    You are under 13 years old.
    You are a convicted sex offender.
    We've previously disabled your account for violations of our Terms or Policies.
    You are prohibited from receiving our products, services, or software under applicable laws.

From Facebook's Terms of Service:

https://www.facebook.com/terms.php