@Rhiannon58 The WA chests are just convenient storage for the stuff that your sims would normally carry around in their personal inventories. They're a good way to keep the clutter down. I personally store my sims' adventuring supplies and loot in there when they're home.
Each location offers a different kind of chest, purchasable at the general store. They're the same chests that your sims open in tombs. In the shot below, from left to right, there are two chests from Egypt, one from France, and one (open) from China. There are also a couple of Chinese vases in the foreground, because they're pretty and there's no point in letting them collect dust in storage.
https://i.imgur.com/rYL71BU.png