I think it's for more floorspace and different types of attachment points to secure gear to the rack. I bought it because it fits between the OEM rails and for the full floor versus crossbars. I think there are better options for more functional racks that have a ton of accessories and purpose built attachments (like Frontrunner, Rhino rack, etc.) but I didn't like how those looked on the LC. hope that helps.Is the purpose of that flat panel design to limit points were a car wash or treat branches could get stuck? I like the design. I've looked at that exact roof rack myself.