Facebook has made a fortune out of a seriously warped version of the word “free”. You give them all your thoughts, feelings and behaviors for free, and they’ll happily sell that info to advertisers. “Sharing” as in “what’s yours is mine and what’s mine is mine”.
The latest revelation is that, by default, anything you share with your friends is also shared with any Facebook app that any of your friends install, even if you have never authorized that app.
For instructions on how to fix this, see When you share personal data with Facebook friends, you’re sharing your personal data with every app your friends use.
If any of you still think Facebook is “free”, please post all of your bank and credit card login/password info as a comment here.