What would providing your own number do? When facebook asks for permission to see your contacts, it says its so it can look through for contacts you have that

What would providing your own number do? When facebook asks for permission to see your contacts, it says its so it can look through for contacts you have that youre not friends with. Its literal explicit purpose is for building out the social graph. And it tells you that. People just dont realize that they would store a phone number they dont have a profile for yet.