Thank you icyclefar, I appreciate your answer. I wondered if this was some kind of user add-on holster securing enhancement device or perhaps a grip adjunct. I know, I've put way too much thought into it already, I am at peace now.
It could have been used to keep it from sliding down the pants. Barrel down the pants and the stud hitched over the belt. It also could've been used to secure to the backboard or frame of a bed. You drill a hole into the frame and put the stud into the hole.
These are just thoughts off the top of my head for whatever it's worth. Lol.