He says that he could take a stroll down that road if he wanted to. He never says that the entire area is playable space. Also every game developer has that whole, "everything is subject to change," line so that they can change things whenever they want. For example snipers used to be a heavy and hand cannons used to be a special but they quickly changed that. They are allowed to change thing at the drop of a hat. Try to remember that the game is already 20 or so gigs so having spaces that big would make the game pointlessly large.