Paper would be more expensive to use, cardboard doesn't exist, and sawdust compacts too easily and turns into a solid wall in the crate from compression due to constant movement. The cotton quilts can be used for anything as long as they're still intact.
@hamsterking5
O . o;
Straw is readily available and typically in mass quantities wherever livestock is raised. Tree barks similar to cork could also be used. While packing in sawdust might be a little too rigid, wood shavings should cushion things about the same as straw. Feathers feels like it would rather expensive and something similar to cattail fluff would fall somewhere between sawdust and straw. Moss and other lichen might offer enough protection, and could see leather tailings and scraps being made use of as well.
So there is a lot of options that could be use, but feel like the author skipped over them because the quilting option was right there and easy to make a connection. When in reality such packaging would only one been used for mid to high end products.