If Mr.X makes a model, and Qwerty Inc. uses it in a commercial render, then sometimes Mr.X will want a rakeoff from the profit that Qwerty Inc. makes using renders including that model. That is a common feature of business. Similar to that in the past I have known book authors to want extra royalties for copies of their books that end up in public libraries, and videotapes are often marked as "not for public showing or rediffusion".