True, marriage has primarily been associated with a religious ceremont, with religious overtones. HOWEVER, marriage can be performed by a priest, a pastor, a rabbi, etc. AS WELL AS a Justice of the Peace, any judge, a city mayor for that matter, so it is also a civil ceremony.
Most gays would be fine with the Civil Union idea if it conferred all the same rights and benefits as traditional marriage BUT its one drawback, a civil union is not automatically recognized by all 50 states the way marriage is. THAT is a problem from a legal standpoint.
I live very close to Vermont, the first state to adopt state level Civil unions.
People that travel from VT. to where I live in NY, a mere 30 min. drive, and BANG! They loose all the rights (medical benefits > car crash > hospital > emergency room > signing/autorizing medical treatment) just cause they hopped in the car, took a 30 min. drive, and crossed the state line.
So if we even adopt civil unions on a national state by state basis, we must forever stay within "our state" if we want full and equal protection.
Somthing to think about.