I think you're really confused about morality.
I think you are wrong. Legislation is based on well-being and morality. Laws governing sexual conduct is an example.
I would offer an argument here, but instead, I'll just say that it's irrelevant. We're talking about morality, not law. Law is determined by any standard the country wishes to use. Law is arbitrary. Saudi Arabia legislates based on Islam's holy scriptures. They are even going to allow women to drive vehicles because after reviewing their holy scriptures, they determined that their faith doesn't prohibit women from driving. Now, Canada doesn't legislate based on holy scriptures. So if a certain country wishes to legislate based on well-being and morality, then that's what's going to happen. So your claim that legislation is based on x is a faulty generalization—regardless of what x turns out to be. Law and morality are simply separate topics.
A person that drinks, eats, parties and is a slob, etc, as debauchery is defined is not harming anyone. But is he moral? If not, because you say so when if he is viewed as such by society?
I would argue that if someone drinks excessively (debauchery is about excessive indulgence in pleasures), then he or she is most likely harming someone. That would be immoral. So let's just say this: if you excessively indulge in non-specified pleasures without affecting other people, then I can't see how you're being immoral. That could be irresponsible, but not immoral. But if you excessively indulge in non-specified pleasures that do in fact affect other people negatively (whether they be your friends, family, co-workers, or even your boss and his/her business), then, yes, that's immoral.
Suppose you disagree with society about what conduct is moral? Does morality exist?
Suppose you disagree with doctors about what treatment is best for a patient. Does medicine exist?
That's why cofty asked the wrong question. Your question isn't like asking, "Does health exist?" It's like asking, "Does medicine exist?" Of course it exists. It's just that it relies on a subjective axiom that everyone agrees upon. Because everyone agrees upon this axiom, which is that in medicine we ought to value and increase health, medicine is epistemically objective. Some people may disagree on what's best for our health, but that doesn't mean medicine is entirely subjective.
Morality is the same way. Some people may disagree on what's moral (i.e. what's best for our well-being), but that doesn't mean that morality is entirely subjective. It just means that there are right and wrong ways to promote well-being, and we need to find out which ones are the right ways to do so.
I haven't seen solid proof of morality.
Yeah, that's because you're too confused about morality. It would take a lot to explain this to you, and I don't even know how to do that in writing. There is something that you either don't understand or simply don't accept, but I have no idea what it is.
But anyway, I've already tried telling you that you're asking an illegitimate question. It's not, "Does morality exist?" It's, "What kind of morality exists?" Is morality subjective, objective, or absolute? But you keep asking the wrong question despite the fact that I've tried to make it clear to you.