Well now you are simply trying to replace restrictive, personal morality with some sort of collective morality based on standards of living. This is just as much legislating morality as any other attempt to do so. It also ignores the importance of personal morality, of self-control, prudence and temperance and such virtues. These are surely very important, even to the health of society. To think that you can make a healthy society just by encouraging a sentimental concern with collective standards of living seems terribly misguided. You need at least a basic amount of self-control and temperance among the individuals who make up society.Laws should not be based on personal morality, as in what is right, and wrong for me to do, but what is best for society as a whole, and how much should the government interfere with peoples lives. Trying to make the standard of living the best possible for everyone, regardless of their standing in the society, or their opinions on things like morality, religion etc. Your comment on prostitution being wrong is simply an opinion, not a fact, and you can't treat it like a fact, which is what your doing. If you don't want people engaging in prostitution then go out and protest about it, start a campaign telling people about the dangers of it, and tell them not to do it. But should the government really legislate, and interfere with people's freedoms in such a way? I don't think so, that is not the governments place, it is just harmful for the people in every aspect.
Prostitution is wrong because it encourages the worst in man, the cheapening of one of his most important relationships and aspects to a business exchange and to its most animal and least human aspects.