I think it was just installed incorrect as I have those L bracket pieces too. They just need to rotate the L bracket 180 degrees so it rests on the edge to be flat. Easy enough to fix though. Just pop the rivets off, rotate and rivet again! Unless they intentionally wanted to have a lip in front and back?
@Salue, just got one rack for the Uwharrie Jamboree and Inti is including that L bracket (something new). The purpose of that is to hold objects lower than the bar, so they don't fall off. I personally don't like it because it will bother if you are loading something bigger than the rack floor or if you need slide up stuff.
BTW, got your bolts. PM send.