No, he said "better image" not "better render". As I understand it, he rates a good drawing higher than a good render in terms of artistic merit. I can see that such an argument is defensible, but I don't really agree. Producing a good render is also a matter of realising a vision; it's just not done in the same tactile way. Reverting to the question, I have seen published adverts evidently done in Poser (and often not very well). There are plenty other commercial applications as well. If there were no commercial users, you wouldn't get people stamping "not for commercial use" over their freestuff contributions. Or would you?