The green canvas Gear Bag is big enough for most weekend trips and has a flat bottom, which will be perfect for putting folded clothes into it. The bag is 9"x18", so it can handle a few pairs of shoes a dop kit and the clothes.
The black canvas Roll Bag is the same size as the Gear Bag, but it is slightly less expensive. This bag can be found for around $15. It is a more classic round shape, but it will not keep clothes folded as well as the Gear Bag.
Certainly worth thinking about re-purposing these bags. Another thought is the use of a bag like this with well put together outfit, it is a nice pop of Sprezzatura.