I could. But it "would ruin era's economy."
Players would resell things for cheaper than the store value, making other players buy from them instead. In doing so, no money goes back into the economy, just the players. Gralat packs are bought less often and stefan goes hungry.
Unless, we can develop a trade system for items that can only be dropped, and can no longer be purchased - this reduces scamming, keeps money floating around and makes me one happy guy.