Photographers and their legal rights

Photographers and their legal rights: "A) You have the right to take a photograph where ever you are, though you must remain aware if you are on private property (like in stores or malls) as this will require special permission. "

(Via fotohacker.)

That's a definition of "right" that I'm not familiar with. If I have a right to take a photograph, why would I need to ask for permission?