Quoted from Betelgeuse:I believe the post you are referring to works like a door stop for the hinged panel that houses the lamps. Without it, the door could hit the side edge of the backbox and break lamps or cause other damage. Normally, it should not come in contact with the translite like that, though.
This happens a LOT when operators don't latch the back door. Or if the door/panel latch is broken. In the 90s, this was very common.