I agree !! It's like any vice; one thing often leads to another. If one has chosen a particular path, it is more likely than not that they grab other temptations on the way.
It's not as if they gauge the depth of their perversion. Once the line is crossed, a whole ugly array of choices is opened up. If nothing else it involves them in a unique circle of like-perverted individuals.
Those are my thoughts, EXACTLY.