Useful post. It addresses some of the facile comments above that the Freakonomics article is just about business/pricing strategy, by calling out some of the non-economic opinions pushed in the article. ("Allie is like the ideal wife", Allie is successful because she sees good in everyone, etc.) It's glib and myopic -- concentrating on this little aspect of pricing, and highlighting all the sunny and upbeat sides of being a prostitute, passing over the bad stuff almost completely.
But what are the bad things for a high-end escort? They wrote about how she felt like she couldn't communicate about her career. They also wrote that a lot of the safety issues that plague low end prostitutes weren't issues for Allie. The main bad thing that they didn't speak about were health concerns.