Civil Union vs. Marriage

Some of my super-religious family members and "born-again" Christian friends, who are against the concept of same-sex marriage, because their faith pushes them to firmly believe that marriage is only a heterosexual right as opposed to a human right, would eventually try to sort of give in out of "love" for me, and say, "OK, I'm for a civil union but not for a marriage.". Why can't they see that what "we" are fighting for is not the right to march down the aisle of a Catholic Church, but for equality of civil/secular rights?
I find it hard to further engage in an intellectual discussion with them to demonstrate that civil unions look nice on paper, but don't work in the real world.
Political blog Blue Jersey recently launched the "Think Equal" media campaign to support marriage equality for all couples based on Apple’s “I’m a Mac / I’m a PC” ad campaign. The video ads and grassroots lobbying campaign focuses on the differences between civil unions and marriage.
If you have an open mind and would like to be educated, enlightened, and humored, please click on the following videos:

Think Equal


Check Equal


Barring Equal


Counsel Equal