Skim Milk Marriage?

I think Justice Ruth Ginsburg's depiction of gay marriage in this country as a sort of "skim milk marriage" was quite compelling. There are nine states that permit gay couples to marry. But are they really married when they do not share in all the rights and privileges granted to opposite-sex couples by the federal government? They are only married within their own state. It's like marriage lite. And that's the discussion that is happening in the Supreme Court right now.