I have done nigh over 700 images using DAZ Studio in all hopes of working for Paizo or Wizards, essentially, I shouldn't be doing them for free. However, the BIG TWO for D&D publishing are a company of curmudgeons. There are, in some ways, a 3D Render can absolutely be used to illustrate scenes.
So what is the purpose of the Character and Portrait Folio? To show off what 3D rendering scenes can and will do.
These two were created using DAZ Studio. The purpose of which is for you to use in your scenes or to represent your characters. ;) I can do more complex scenes too. Warriors fighting dragons, Gaeles, Lilends, and soon angels and demons. :) Each image is Creative Commons licensed for sharing. Why do so? Well, one of the crazy things about Copyright is that I have the right to use the media I create as I see fit. If I designate that it can be shared, then I can do so.
After all, it lives in your minds. If they are shared, they can propagate through many channels over the internet.