Just recently the Australian government has recognised gay couples in social security so that if they live together they are considered a de facto relationship, I figure if they are willing to do that then they should give them the right to marry. You can't go half way.
I just think when you ask someone a question you shouldn't expect a certain answer. Miss California is one person, its a Beauty Pagent so as much as they want us to believe they represent the people of an entire State its just not the case. I am personally for same-sex marriage I don't think the rules of Marriage should be based on Religious philosophy but on love and commitment for each other.
One reason people get married in the US is for lower taxes when filing jointly, especially if one person has a significantly higher income than the other.
Why? It benefits the heterosexual couples who are allowed to marry. They want the benefits over the single people. If same-sex marriage is allowed, more people have to file taxes as single.
I see where you're coming from, though.
I don't want to say you're making a mistake, but you are assuming people make rational decisions all the time and that their perspective on life is rational and logical.