That ain't rock 'n' roll... that's Jennacide. And that's the sort of thing that might make this a community if we're not careful.
Myself, I'm hetero enough to make your eyes hurt. Hetero enough to have understood for a very long time that I'm not likely to "catch gay" from anybody. Maybe I shouldn't have a dog in this fight (the status quo in most places, after all, very much favours me over those who differ from me, so why make waves?), but I do. Gay marriage is legal here, and has been legal for long enough to have become almost ordinary. Ordinary, that is, in the legal sense of things. But that doesn't mean that people -- individuals, families and sometimes friendships -- aren't being torn up over the issue.
Maybe there was a time when these prohibitions and taboos made sense. When the size and strength of your family and tribe made the difference between survival and extinction, then having people seem to drop out of the reproduction industry might have been a real danger. We're nowhere near that world anymore. The population of this planet has doubled in my lifetime, and we're getting to the point where reliably feeding all of those people over the long term is going to need the kind of restraint and cooperation that we've so far failed, as a species, to demonstrate. So let's take the "marriage is for having kids" thing off the table, shall we? (For Americans, that'd be, "lets table it". We keep our current business on the table; I have no idea where you guys are keeping it, or why you'd want a bunch of stuff you're ignoring on the table.) It's a spurious argument, and it won't be long before it becomes a suicidal one for the species.
As for religion, well, whose religion? There are a lot of them. If anyone is right, then at least one of them must be wrong. Maybe got the message a little garbled. Added a rule or two that didn't come directly from the Eternal. I'm an atheist, but I'm not an antitheist. Let us, for the purposes of this argument, presume a God. And for the sake of the traditions of my local culture, let's use the masculine form of grammar. The question then becomes: if God hates homosexuals so much, why did He make so many of 'em?
As for the tradition of marriage in the Christian church, well, the church never created the union. It was the job of the clergy to examine any legal impediments (fraternity, consanguinity, existing marriages), to determine whether each of the couple were entering freely into the union with the intent of remaining together permanently, then consecrating the union. The marriage already existed, the church merely blessed it while the community celebrated it. The Roman Catholic idea of marriage as a sacrament is relatively recent as these things go (it's post-Reformation). Civil definitions (the union of one man and one woman to the exclusion of all others) were made by people who I don't think for a moment would have been able to conceive of gay couples wishing to marry.
Cripes, we're barely forty years past Stonewall. A quarter century ago there were a lot of people dying, a lot of emotionally damaged people who had lost the ability to form relationships because we wouldn't let them. I lost friends in those days, friends who believed to their roots that there was something wrong with them. AIDS was going to happen, period, but GRID spread the way it did because we created the conditions for it to spread.
It's about time for a great popping sound as millions upon millions of us pull our heads out of our butts and recognise that we all need to love and be loved. In the end, that's all that ever counts.