The only way I can see prostitution as ethical is if someone can choose to have no job and be fairly comfortable.
But that wasn't the condition that the OP said made him comfortable. He said he'd be okay with legal sex work only as long as the person could otherwise live a life of comfort without the need to work. He didn't say he'd be okay with legal sex work as long as the person could have chosen to carry a bag instead.
Why is 'forcing beliefs' even at question, you surely don't think whether you're forcing your beliefs on someone when the issue is carrying luggage?
Or, maybe they're different classes of activity and you already realise this ...
You feel differently about someone charging for sex than someone charging to use their brain or their brawn, but that does not mean that everyone feels the same way. Why should your feeling rule the day and be enforced on adults who feel differently about it? Sounds like the church of old.
My initial post in this thread was about the legality of consenting adults engaging in whatever activities they both agree to. I tried to highlight the distinction being made and think it has a lot to do with slightly prudish notions of sexuality and frankly a notion that men and especially women aren't capable enough to make the correct choice for themselves.
Attitudes change and in my view it's time to stop being so emotionally negative toward sexuality and the diverse choices made among consenting adults.