Why do some people insist that others follow some moral code as they believe?
Because they need validity in having others follow their way of thinking. Their spiritual/moral egos are so fragile unless others pay heed to their moral code, they feel threatened. In reality if you do not believe in homosexuality, it is easy to avoid dealing with gay presence. But you say it permeates the culture. So does meat eating but I manage as a vegetarian to deal with it. And yes sometimes it is challenging but if I believe in vegetarianism I deal with it.
There is an ethical question that occurs about morality. It goes like this: if I never face temptation can I be truly called moral? In other words if you have a lifestyle that is never challenged by temptations or made hard have you really made a moral choice? Is the choice merely something you grew up doing? If I have never cheated in my marriage but have never had an occasion when an affair was possible can I really say I am faithful husband? The fact is you do not know because you have not had the opportunity to cheat. So when people demand that there be laws legislating morality it makes me wonder is it because they fear on some level if the opportunity occurs they will not be faithful to their morality. Just a thought.
Another reason for demanding others follow your moral code is you have a penchant to want to control events, people and things. This is what is known as the God syndrome. Now God has given us free will and choice but you somehow think this was a mistake. You believe you can out God God. So you desire to take free will out of the question so you can create a better world. We all know this free will thing was a mistake and you aim to fix that. You are uncomfortable with the separation of church and state. Because in a democratic state the government tries to involve itself as little as possible in the affairs of humans. But in a church state you can condemn personal actions of others and punish them for these actions. A church state is very interested in involving itself into the affairs of its citizens.
The final reason I will address today is the so called love factor. I love the offending moral lapser so much I am willing to inflict emotional, spiritual, legal, and even physical pain on them to help them live a moral life. But of course the fear of punishment does not make them moral. It makes them scared. Another ethical question that is batted around does the motivation of the fear of hell or the promise of heaven make one moral? Many say no. You see fear or an award does not too many in the final analysis make you moral. It merely makes you a survivor. The moral person is someone who will do good even when there is no promise of reward and is willing to take the potential horrible consequences of his/her actions. I will live my values in hell or as some Holocaust survivor ethicists have proclaimed in a holocaust camp because I am a moral human.
Now that is some pretty tough stuff. And to be frank to live like that takes an unusual strength. And to me that is the final reason I do not try to force my morality unto others. It can be hell to follow your values and I believe everyone should have the free will to choose what hell they want to live in. Or to put it another way everyone should have the right to choose the heaven they want to thrive in.