My brake controller only has power when the 7-pin is connected.
With a Ford you do not have to disconnect the 7-pin overnight since it is cut out by a switch when the Ford's ignition is off, but with a Chev it stays live with the ignition off, so you always unplug the 7-pin once parked for the night.
If you want the trailer to be level overnight, you usually have to unhitch and raise or lower the front of the 5er. So you would be unplugged for that night too.
Some places the truck sticks out too far so you have to unhitch anyway. Sometimes you want to use the truck and leave the trailer there so you unhitch anyway.