When I picked up the car at the dealer, they took a bunch of things from a ziplock baggie and put the owners manual in a plastic slip case emblazoned with the dealership logo, with sections for ownership and insurance slips and room for service records and other things that should stay with the car. I assumed that the factory packaged stuff that belonged with the car, like keys and radio codes and manuals, in the ziplock baggie to keep things handy. It does seem strange that that's how your dealer gave it to you.