The classic view of the state was that it represented a people. It's function was to represent and protect the interests of a people.
Therefore, the state was responsible for protecting the people from enemies and invaders, the integrity of the borders, and the general welfare of the people. There are 3 basic ways to eliminate a people - annihilation, infiltration and dilution, and finally, infertility. So, the state, along with it's general function of protecting life, limb and societal cohesion, has a corollary function of promoting the continued production of the people it represents.
When you get into the modern view of the state as simply a geographical monopoly, it's interest in promoting the continuation of any people becomes a little murkier, but is still there. After all, it's difficult for a state to continue when none of the people believe in the ideals it espouses. So therefore the state must encourage the production of the people that do believe it's organizing principles.
Okay - I see where you were going with that, then.
But the state having an interest in promoting marriage as a means to reproduction and cultural unity is not the same as having a right to usurp the religious sacrament of marriage vows and blessings. That's what the Church is supposed to be about in this respect. The Church should never have bowed to the state's desire to license marriage. We the People should never have submitted to manipulation through the tax code. The fact that these things are already in place does not excuse it as right or just. This goes back to something I posted early in this thread - to the effect that The Church should never have participated in this joint-ownership of the marriage rite.
And - just to get back to the OP - Two preachers and a building doing weddings for hire does not constitute a Church. Not in my view, anyway. I suspect that we will soon find out if the courts hold that same view. The implication at the beginning of this thread was that the owners of this wedding chapel were being charged, but that is not factual. The truth is that they have filed a preemptive lawsuit against the ordinance....
http://www.ktvb.com/story/news/local/regional/2014/10/21/wedding-chapel-sues-gay-marriage/17681477/
