Likely because a large portion of the people who are employed at these venues are, generally speaking, more vulnerable and susceptible to abusive cycles and behaviors.
I have known and been friends with a few people in the sex work trade throughout the years and generally they didn't end up there because they came from solid foundational bedrocks of self-care and self-advocacy growing up.
Of course, that's not to say that my anecdotal experience is empirical, but I'd wager reality sways a little closer to what I've seen than the opposite.
