This situation would be very complex, if you've ever read the book 'Private Dancer', written about Bangkok, Thailand it'll open your eyes a bit. It's actually available to download online.
If your going with a prostitute, you'd be giving your relationship a rough start and could even end up destroying your relationship through trust issues. It would be a situation where you'd need to go in with your eyes wide open, and not let love overide common sense and logic.
No-one should feel more righteous then another because they first met there missus in person, online or in a bar. Life isn't about that, we are equal at the end of the day right? Or are some people more equal then others?