What's the diff?

Today civil unions are legal in New Jersey: all the legal benefits of marriage, without the title. There are people who think that it shouldn't matter, that there's no real difference, that everyone should be happy now. But I don't think they have thought it through. If there is no real difference, then why aren't they just being called marriages? If the name shouldn't matter to the gay couples, shouldn't it not matter to those who oppose their marriages? Of course it's not really about the name, it's about the intention behind the names - it's those who oppose gay marriage who give weight to the difference between "civil union" and "marriage" by denying the latter.