WTF has the church or state got to do with marriage anyhow. The church can bless the union of two, or more, of its members if it wants and can have its own believes around that. The state only needs to know that a couple (or more) are now a single legal entity so providing that is register as such, like a mini limited liability company then the state should be happy and keep its nose out of it, call it a registered union.
Marriage is a special bond between the people involved and is not reliant on any outside organisation, more reliant on the families and friends of those involved than religion, cult or state.
If and when kids come along they register that they, as the registered union, are responsible for them, your choice whether you consider them liabilities or assets 
Marriage involves leave others to be with the chosen, declaring such, and cleaving with the chosen partner to become a single unit.
The trouble with this law's chosen course is that once they have the state given right to marry they will try to use the state's anti-discrimination laws to try and force others such as churches to recognise their 'marriage' and perform the ceremony. How the hell you can want a group that doesn't like you to perform the ceremony is beyond me but I guess it is no different from a traditional bride deciding she likes the look of that cute church she has never been to and being upset when the priest tells her to take a long walk off a short pier.
Great minds discuss ideas, average minds discuss events, small minds discuss people. --- Unknown sage
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