You're right, the availability of sex and sexuality is too much for men to handle. We should criminalize prostitution - and while we're at it, why not criminalize yoga pants? I know those are pretty tempting to me.
Um, no. Things like murder are criminalized because they involve the infringement upon the rights of others against their will. Prostitution does not infringe upon anyone's rights against their will.
But once you receive the answer to your real question, the reason why prostitution is criminal, while yoga pants are not should be self evident.