Because the "poses" in Poser are dial turnings. Inherant to the software. And can't be transfered to any other software as a poseable function, only as static props. Thats the data involved and the use of the data. The pose 'itself' can't be copyrighted because nothing can be copyrighted that existed before what is it, 1927 or something like that. And there is NO pose that hasn't been made by the human species.