The software exists, but its far from the point where it has any logical implications for this stuff. Coming from someone who's been doing this for many years, i can tell you building it from scratch is far easier in the long run. Getting the dimensions right, the textures, bones, and rigs will surely take time but the fully polished and finished model will be much more stable for general use. Ive worked with scanned models, and models 'Generated' from pictures and in the end i spent more hours prepping the mesh for practical work then i would have actually building it myself.
The whole problem with the CG side of inflation, is logistics. To create and render High quality work, you need a slightly above average computer or more. You need almost as much technical experience, as artistic. Depending on the details it can take days, or months to create a fully functional character for use, not counting animation or render time, as well as 'debugging' if you fucked it up. In short, drawing pictures in thirty minutes versus days of work, or months of work just makes sense, especially if you're new to either drawing or CG.
It would require some experience in 3D programs use the proposed software in the first place because of all the clean and polish work. Anyone capable of that alone, will have better chances doing the work themselves.