[users] connect by sharing; sharing thoughts, notes, opinions, pictures, videos and everything else that builds makes them a personality online instead of just a username. The marketers and websites that use data provided to them by Social networks use it to provide a better experience by serving personalized content. Wouldn’t you rather have that then being served a standard page with irrelevant content?
The sooner the illusion of privacy is shattered, the better it is for users who will make smarter and wiser decisions about what they share and where. As for the battle with privacy, that is over. Privacy lost. Connecting and sharing won.