Well the case of phone number information is even more devilish - it is in the phonebooks of your (not so privacy-savvy) friends so you have almost no control over it.
This is the worst part about your contact details, just think about the number of times you get those spam emails when one of their accounts gets hacked, not to mention address books mobile APIs.
Now think about how they often contain your home address, birthday, spouces, photos etc...
