What preferential treatment is that? Seriously. Is there some preferential treatment going on with this law?
Good question. Concerning this specific case, I concede - no. But this ruling has ramifications outside this specific case.
One thing comes to mind, domestic partner laws, which entitle same sex couples to the same benefits as married couples. Yet, they don't pay the "marriage" penalty taxes. They don't have to undergo the legal ordeal of a divorce, if they break up. Heterosexual couples, who are intimate, but not married or people living together, who are just roommates, are left out. And it's based on what you do in your bedroom.