There are of course many photographers who work completely outside of the assignment-photography mainstream, and I admire their tenacity. However the truth of the matter is that there is no such thing as a pure artistic practice.
After all, the fine-art and gallery circuit is simply another type of market, with frustrations that I think equal or surpass those that come with shooting commercially. I can only speak for myself here, but at the end of the day I would rather try to second-guess an ad agency’s expectations than attempt to parse the semantics of a grant application, or, God forbid, another pretentious and willfully obscure artist’s statement.