He has a leather belt because it's better than the plate alternatives if you don't need the hit rating from the Malevolent Girdle.Originally Posted by Samurai
As for the gem, I'd guess he was planning to switch the Nightmare Tear in his chest to a Dragon's Eye (because he's not going to replace it for something better any time soon) and didn't want to waste an epic gem in his boots when he'll be putting a Nightmare Tear in that socket.