It is discouraged though. Women didn't have any rights like they have today. Often if a woman was divorced or not married, then she'd be subject to a life of poverty. They didn't have the conveniences of modern society, like welfare, women having the same or better jobs as guys, and were often viewed as property. In this context, women would have to do sex work just to eat to survive because she needed a husband to survive (ie despite this, of course, not all women did this)sex work has been around since Biblical times.
In Western society, I don't feel there is justification like that for women to do that like in Biblical times. I do get there are other "issues" and spiritual forces that can make people do sick things or make bad decisions in terms of lifestyle. However, like you said most of these types of women don't do sex work and manage to survive without going there.