On the prostitution thing, I don't think it's as simple as willing buyer, willing seller. For one thing, the buyer and the seller don't have equal standing in that kind of market. For another, patriarchy is a set of power relationships that colors just about everything. Nobody asks a powerful person if you can buy sex from them. There's only an expectation that people without power will have sex with random people for money.
Maybe it would be different in some Utopian world where everyone was truly equal and sex wasn't laden with so many complex elements of status, danger, shame, compulsion, vulnerability and other aspects of hierarchy. But that's not the way it is under patriarchy.







