That all human interactions are exchanges of value and to that define consent in such a way that it cannot be purchased is to define it in such a way that it’s totally useless as a word. If you eat meat, you’re a murderer, you buy from a capitalist enterprise you’re a slaver, you hire a sex worker, you’re a rapist-- but it doesn’t do anyone any good to throw words around that aren’t useful for predicting an agent’s future actions. Every relationship in which both sex and money are important, which is most of them, is some percentage prostitution-- and banning it deprives people of the ability to negotiate their relationships clearly. The inverse of its incidence should be used as a barometer of social progress, but in terms of actual policy it should be decriminalized. In “Make Way for Winged Eros”, Kollontai observes that aside from labor dereliction and attempting to leverage sex-love as a means of creating comradely bonds, there’s no basis for banning sex work. I think this follows from materialist epistemology in a very straightforward way.