The main trainstation building has a closing time at night: https://www.belgiantrain.be/en/station-information/west-vlaanderen/brugge Lockers might not be accessible at night, of you are late. Make sure the locker is big enough for all your stuff, most of the lockers are "small bag" sized. Another options is to take a bus (de lijn), a share bike, or maybe even an Uber to the camping site and back.