Like a case of broken windows [1]. One could argue if such wanton destruction of the Orangutan habitats wasn't occurring in the first place, then there'd be significantly less incidence of Orangutan prostitution.
The destruction is not only precipitating Orangutans destined for premature death available to the sex traffickers, it's also setting an example of total disregard for their lives on a massive scale. What harm is there in exploiting them briefly for profit before they die? (Not my position, but I can easily imagine that thought process being real for the traffickers.)