This has been asked many times before, and I always give the same answer: I'm pretty sure that Michelangelo did not manufacture the table he used as a prop in the famous painting "The Last Supper. Nobody questions him as an artist for that reason. If you throw in a table prop somebody else made in your Poser scene, why should they question you? "Art" is about the message the image conveys, not the process that was used to make it. There is a difference between "artistic" and "technical" aspects of a picture. Both can be discussed, but they should not be confused with each other.