You will probably see plenty of packing types, I would think you'll see some MDTR, KSHB, and a few other players in the packaging space.
Which reminds me of a story a family friend told me he did before Amazon went big. He invested heavily in Amazon, but also he looked up who they were using for card board, foam, and other packaging materials and invested large in them as well. He literally died a millionaire and his gold digging wife is set for life while his previous 2 wives and children got the shaft.