Akeneton, you've raised a slightly different spector recently. It sounds a lot like you're implying that it would be better if homosexual activity in and of itself were still illegal.

In my own experience, when more "casual" Christians are adamently against gay rights, in many cases they will sooner or later mention that they have heard that homosexuality is condemned by the Bible, and relate their stance to that.
As to folk who simply object because they were raised with objections to, and raised to object to, such things as a simple matter of generalised cultural tradition: that brings us right back to the sort of thing that has already been mentioned repeatedly already. Many, many people felt that their valued traditions were violated when the laws against interracial marriage were overturned.