Its 'free', and you are the product (Congratulations!). You pay with your metadata (address book). Metadata is invaluable. Facebook knows everyone's connections. I'm even included in someone's address book, even though I don't use WhatsApp or any other Facebook service. I'm not benefiting from Facebook's free services, yet I am the product. It is disgusting, I hate this company, but I can't blame them. They get away with their nefarious crap for fun & profit.