Who's to say what the difference is? Who has the authority to say so? In a morally relative society it's anyone's say...Is is merely an age of 18 or does the circumstances change the definition?
Do you mean in a "free" society people decide and vote on what laws should be appropriate and just? I thought a "free" society meant that anything goes --sarcasm.
Yes, and kiddie porn is outlawed as it should be while adult porn is legal. I am not sure why people have a problem with what consenting adults choose to do. I don't always approve of those choices, but as long as they are not illegal and don't hurt those involved....I don't care.
Nope.
In a "free society", government gets involved when another person's rights are being violated.
The model you suggest is three wolves and a sheep deciding (and voting !) on what's for dinner.