I think you're just being deliberately obtuse here, but anyway here goes: the OP is pointing out the restriction of choice, not what the choices are. You won't

I think you're just being deliberately obtuse here, but anyway here goes: the OP is pointing out the restriction of choice, not what the choices are. You won't find a restaurant that serves both Coke and Pepsi. Whether you can go to another restaurant or whatever is completely beside the point.