Interesting link. A couple of months ago I had a discussion about this with Lee Varis, a Hollywood photographer and Photoshop guru. One of the things he pointed out was that in the majority of movie marketing materials like posters etc, the heads of the stars are pasted into the photograph on other models' bodies. This is a much cheaper way for the studios to have marketing materials made. In fact much of his work was creating photographs of models in various environments and then adding the stars' heads later, this way the stars did not need to be present. Hence much cheaper.
Good information and it does make sense. Those are one of the things where it does not seem unreasonable, movies are all an illusion (in a good way) and marketing materials for a movie seems to me an okay use of those type of techniques. Perhaps it is just because I do not expect it to be real to begin with.
Sort of the along the same lines, sometimes on DVDs there is bonus material of deleted scenes or other similar material that has not gone through real post production (such as color correction). I love looking at those things to get a sense of what was "real" and how some post production is used.