It's also possible it controls a line that has been run to the outlets in the room but not actually hooked up to any of them. In our house the switched outlet line runs to all the outlet boxes in a room but is only hooked up to one or two of them, so you can easily change which outlets are controlled by the switch. Theoretically it could be a situation like that, but with no outlets actually wired to that line.1) It is not tied to any outlets in the room