Fair points. That's why I added a strap running inside the pocket to cinch contents to the leg. The fabric is also thick enough to hold its shape to some degree so it won't swing too wildly for medium weight items. But if you want a general purpose folding pouch for your belt, you can buy what is called a "dump pouch" 👍

Edit: also the pants falling down is remedied with a belt or suspenders, just like with regular cargo pants.