Gnosticism is not a term that can be used to define a uniform metaphysical system. There are a variety of metaphysical schools that are bundled together in the modern usage. For example, in what German scholars of early 20th century came to call "Iranian Gnosticism" (in reference to Manichaeism [1]) it is in fact the Father of Light that "sacrifices his sons" as 'food for daemons' so that the battle between Light and Darkness is taken to 'their turf'.
> Capitalism
Interestingly enough, another Iranian gnostic school derivative of Zoroastrianism - that of Mazdak [2] - shared everything, including "women".
In general, one should be careful to be quite specific as to what metaphysical school of thought they are referencing when using the currently ambiguous term "Gnosticism". ~
Mani's metaphysical vision is rather wild. I was just reading up on it the other day - apparently he even resorted to diagrams to make things clear.