Because I don’t want to worry about finding a new backpack every time I just have everyone have 2 backpacks for selling items, then just before I sell I go to everyone’s backpacks and just mark everything as wares. Although, honestly I started doing it because I wasn’t positive that it was giving me the price for the items in the pack and not just the pack itself early on. It’s routine now.
There’s also some perspective in play here. It’s up on a hill and a distance from the camps. From this POV it’s going to look a lot more imposing.