What we actually have here is two differing philosophies about ownership of data.
Google believes your data is portable. They believe that once you import data, you own it, and you should be able to export it. If you give me your phone number, I know own that data. Example: If you decide you don't want me to have your number any more, you can't do anything about it. You can't make me forget it or tear up the piece of paper I wrote it down on. You shared it, I imported it, it's now mine.
Facebook disagrees with this. Facebook believes that the phone number only belongs to the person who's phone it is. They believe that if you share your phone number with me, I have to give it back and forget about it if you ever ask me to. Because of this, Facebook does not allow integrating contact info. They only allow Facebook contact data to exist "along side" your other data. So if someone unfriends you, you lose their contact info, picture, etc.
Google, on the other hand, recognizes that this is fundamentally stupid. If you share your data with me, I can keep it if I want, and I can export it to my contacts list if I want and if you don't like it then don't share it!
Facebook takes their position under the guise of maintaining that "only you should have ownership of your own data." But in reality they are enforcing the presence of Facebook if you want to use data obtained from Facebook. In essence, they are asserting that Facebook owns your data that you share.
This is another example of Facebook's dangerous philosophy about "openness." They call it open, but really it's Facebook in control. Meanwhile Google lets you pack up and leave and take your data with you any time you like....