Civil unions are NOT equal to marriage they do not carry the weight nor come with the same legal benefits / protections
It seems there may be quite a bit you dont understand about legal marrage.
People that get married in church are NOT considered married by the state unless they and the church choose it to be. Most churches have the power to marry just like a magistrate or ANYBODY that applies for the power but a religious marriage does NOT guarantee a legal marriage.
Notice the part of the vows where the preacher, pastor, minister, Rabi etc etc will say "by the power invested in my by the state of blah blah blah, I know pronounce you husband and wife"
With out that power given by the state and people applying for a marriage license religious marriage have NOTHING to do with legal marriages unless the for mentioned is done.
SO no simply getting a religious marriage does NOT give you legal marriage, there are churches that marry gay couples right now and they are not LEGALLY married because that state currently discriminates against them.
Also the reverse is also true, I can get married by singing elvis or a magistrate or anybody that has the power to do marriages and it will have nothing to do with religion unless I chose it to.
Hopefully you understand now.