Let me try in basic non-sarcastic mode and see if I can get the message across better:
All law regulates behavior. The purpose of law is to decrease objectionable behaviors (that is, those behaviors that are harmful to society such as murder, child molesting, and homosexual behaviors) and to increase good behaviors (such as marriage between one man and one woman, working for a living, and respecting property rights)
Using the law to enforce good behavior is as old as law itself and is the only way for any society to survive.
Pretty simple concept actually. So we do have the right, in fact we have the duty, to tell people that certain behaviors (such as murder, child molesting and homosexual behavior) are harmful to society and won't be tolerated and to encode those 'tellings' into law.
Yes
child molesting
Yes
and homosexual behaviors
No. The first two cause actual harm to an innocent other person, the last does not.
You have a very subjective and self-serving definition of "harm". If homosexual behavior causes harm to society, then by your definition so does fast food, tobacco, and alcohol. If you want to open the doors to that kind of big nanny government dictating that bad behavior is illegal, you certainly aren't a big fan of living in a 'free republic'.