Do you think it is because they want to create an alternate reality for themselves, frank, because they view their real lives as bleak and useless or is it something else?
I think it depends upon the primitive.
The lying titty primitive, for example, seems to want to create an alternate universe for himself.
The burdened primitive, for another example, seems to view his real life as bleakly useless.
Ms. Ed the unappellated eohippus, for a third example, was simply born a liar.
The Bostonian Drunkard, for a fourth example, lies to escape reality, but in reality, the Bostonian Drunkard's lying only to himself.
Doug's ex-wife, for a fifth example, lies because the pharmacueticals make her lie.
There's some fine distinctions as to the reasons primitives and sub-primitives lie.