How is /that/ suddenly "creepy"? I find it creepy that people upload their complete lifes onto Facebook and agree to be stalked 24/7 by Foursquare et al, even

How is /that/ suddenly "creepy"? I find it creepy that people upload their complete lifes onto Facebook and agree to be stalked 24/7 by Foursquare et al, even actively "checking in" (never understood what for) to publicly broadcast every movement they make.