Yep. I've been staring at those battens and backed out staples for years. I've tapped them back in, and they work their way loose.
Some of my batten have broken on the fingerjoint behind the photo-finish too.
I think about replacing them and the push boards (one is shown in your shot) with some solid alder or oak battens from my cabinet supplier, but it seems like a lot of work. Instead of stapling directly into the aluminum, I would use small screws.
It's really fun when we winter camp and I wake up to see tiny ice chunks condensed on the protruding staples.
I've had a few work their way out but not that much. Maybe put a very light coat of polyurethane non foaming adhesive on the legs and tap them back in?