The Caves of Chaos is a dungeon out of one of the first D&D modules, B2 Keep on the Borderlands. The caves are inhabited by kobolds, goblins, hobgoblins, orcs, ogres, bugbears, quite a few different monstrocities, and finally the Cult of Evil Chaos. The hobgoblin leader, for example, has nice furnishings, while the rest mostly have cots. The kobolds on the other hand sleep on skins or skins stretched over a frame, or just piles of rubbish. The adepts and acolytes of the cult sleep on expensive beds with dressers and braziers.