The basic thing is... It's not important if you understand why people do it. (and that is not a personal attack I mean the collective you) If it doesn't make sense to you, then YOU won't do it. All that matters is that it makes sense to someone else and they DO do it. Art is about realizing "real-izing" your own personal inner vision. People use all kinds of different tools to do that and there are all different kinds of art out there. Is performance art less worthy because you can't hang it on your wall? How about music? What is important is the final product, not the genesis of the materials that allowed you to achieve it. Art is simply another form of communication, a way for people to express some part of what is inside them. If someone makes a model and makes it available to others and that model fits my needs to allow me to realize my vision, why should I waste my time trying to make it myself? As zorares so wisely points out, most artists would not be criticized for buying their paint and brushes. I cant recall hearing of a musician that feels they must create their own instruments. Why should digital artists be criticized for buying the materials they need to create THEIR art? The only thing that matters is the final image. If it expresses what the artist wants it to express then it doesn't matter how it was made (provided the means remains within the bounds of social responsibility. i.e. I am not advocating holding another artist hostage and making him paint your vision, or encouraging the psychotic episodes of anyone that feels they need to make their art from human body parts or something) and it doesn't matter if models are bought or made or if the image was post worked or not. In art, the final image (or production or song or book, etc.) is all that matters and the only person capable of judging it is the artist that created it. Everything else is simply biased reaction to the artists work.