If you build a man a fire, he'll be warm for a day.
If you set a man on fire, he'll be warm for the rest of his life.
However, not all forms of incest that are illegal are harmful. First cousins having children only raises the chance of a genetic disorder from 2% normally to 4%. This is a small increase, especially compared to other things that can increase the risk for offspring to have genetic problems. There is no chance of genetic disorders from two people of the same sex who are closely related having a relationship or from an incestuous relationship where one is infertile or cannot have children because there is no chance of offspring between them.
Then the subject goes to undue influence. This undue influence would be most likely to happen when the older participant in the relationship was a major influential factor in the child's life or when there was some abuse/neglect happening in the family. This really isn't a factor if the younger of the two is older when they meet, such was the case in a legal battle that granted two siblings the right to marry when they met after they were adults.
There are logical reasons to object to some forms of incest, but that doesn't mean that people haven't gone too far in what is considered incest. Some states/countries do/did have laws that included in-laws as incestuous relationships.
"A woman is like a teabag, you never know how strong she is until she gets in hot water." - Eleanor Roosevelt
Keep your religion out of other people's marriages.
As you can tell, I'm not a big fan of drunk people.
These people are. or are possibly, impaired and thetrefore cannot make sound decisions for the themselves. They need to be, and, generally, are, protected by law from things like this.What if the sadistic billionaire offered someone high on drugs, or a heavily addicted drug addict? What if they offered the elderly, or mentally impaired?
Otherwise? I see no moral issue. Have at it.
I'm curious where this ends?
Why stop at prostitution and eye-gouging?
There are countless professions that require someone of limited means to perform some inherantly risky job in exchange for money.
What about the fireman rushing into a burning building in order to save the life of a millionairess debutante?
What about the inner-city kid working his way up the the amature boxing circut toward a chance at a prize fight?
What about a guy manning a swordfishing boat on the North Atlantic?
Where do we draw the line between jobs that are potentially dangerous and should be illegal and those that are of equal or even greater danger but should be perfectly legal?
Or is there no line?
Should it be illegal to assume any degree of risk, or expose one's self to any degree of danger, in exchange for recompense?
If they satisfy the conditions for legal consent (are not under influence/threat, are not impaired in decision-making) then yes. And I agree that prostitution should be legal. Let me go find that poll.