So what is the problem? the light goes on and off with the switch. What else do you want to happen?
I suspect you are using a digital meter and getting a phantom voltage reading.
We are now looking at the diner wire box, that is the one you questioned the wires and what they did with the switch on or off.
Not using a digital meter. Just a probe that you touch the wires with. Lights up green, red when hot.