Because there's a difference between, "oh look, JustSomeNobody just went into the mall" and "JSN went into the mall, then he bought a slice of pizza, next he sat in the massage chairs. After he got up from the massage he went into the As Seen On TV store and bought some cheap doodads. Finally he exited the mall 45 minutes after he entered it."

Also, while anyone _can_ take a photo or video of you, they cannot do whatever they want _with_ that photo or video. If they use that photo to portray a scenario that simply did not happen then they can be in some serious trouble.