I see nothing wrong with selling titan runs. Completely adheres to the rules of the game. Now if you go buy gold from a gold seller, then you do so at your own risk. The primary way to make money in this game is through the market, and there are thousands of ways to do so. If you choose not to participate in creating and selling goods to make money then you will have to wait till SE adjusts drop values on mobs/bosses. Which they may never change.