What can you say about a Military Bag.... Everything! If it was meant to carry somthing, conceal it from the eyes of your would be assasain.
Then the Military already thought of it.
Ancient Romans had Bread bags, Cowboys had Sleeping Bags. Frontiersman used a form of a Ruck Sack. or a Sling Bag.
One of My Favorite bags is the Bread Bag. that the Prussian Army Carried.
Whatever your Need is, the Military's from around the world probably already Made it.