I get your point but most do see a marriage as something with high value, her jumping from man to man imo does devalue it. But then again I did go to a catholic school
In terms of the church and gays they will never be cool with it. Mixed race marriage opinion was rooted in racism and bigotry there was no biblical argument at all. There IS with non heterosexual marriage. The church do have a strong biblical reason why they do not want to allow it to happen. In order for a marriage to be classed as a proper one you have to consumate it. And in order to do that...well you know what has to happen
and Leviticus says that's wrong. I'm Christian and LGBT so I kind of don't listen to that. But I see why there is a furore over it. It kind of goes against what they stand for, respect for the Bible in the modern age. It's what it is. Gotta deal with it.
Actually there were plenty of Biblical arguments bandied about by anti-miscegenationists and one of the judges in Loving v Virginia even said that God separated the races and so it was against his will for people of those races to unite themselves in marriage.
Plus not all Churches are against gay marriage. Quakers, Unitarians and Liberal and Reform Jews are all in favour and want the right to perform gay marriage ceremonies. The Church of England is also incredibly divided on the issue with even some bishops calling for the Church to allow same sex couples to marry. The Lutherans in Denmark and Sweden already marry gay couples. So it's not all that clear cut really.