Pretty Lame argument dumbass -in fact you're simply attempting to deflect the heat away from homosexuals - sorry pal - it doesn't work.
It works perfectly well if you apply the 'productive sex equals morality' standard consistently. If unproductive sex is evil, then it would follow that productive sex would be good.
You say it 'doesn't work'. Why?
And if you're just going to arbitrarily ignore any non-productive sex that doesn't fit your model or ignore the 'productive sex equals morality' model whenever it breaks.....then your standards are hopelessly subjective and superb examples of cherry picking.
Either the 'productive sex equals morality' standard works. Or it doesn't. Its one or the other. It isn't valid when you think it works and then suddenly becomes invalid when its inconvenient to your argument.
Immorality attaches itself to any sexual activity outside of the Divine design to create a family, whether children are possible or not. In Pope John Paul II's "Theology of the Body" the case is made that sin enters when the pleasure of sex is made into an exclusive objective for sex.
But what if someone doesn't subscribe to your religious interpretations? You are using your faith as the basis of your assessment of immorality. And faith is about as subjective as it comes. And of course, religion is ridiculously subjective. You speak of the harm of adultery.......the Puritans killed adulterers and those committing sodomy. The founders only killed for sodomy. Modern day Christians in the US don't kill either.
So who is right? Did God's law change over the last 500 years? Or did the interpretations change? Or is it possible that you *all* got it wrong? And these are merely changes in the same faith, in the same cultural tradition, in the same general area, using the same language and the same religious texts.....separated merely by time.
If you go between cultures, between religions, between regions, between languages, between texts, you get even more radically diverse differences.
And almost all religions are mutually exclusive. It can't be BOTH Jesus and the Greek Pantheon of Gods. Which means that only one can of these mutually exclusive religions can be right. Which in turn means that ALL others are wrong.
Which means that by default, almost all religion is wrong by the very logic of theism.
And its so much worse than that: there's nothing that mandates that ANY religion got it right. And even if one managed it, religion is subject to time, personal interpretation, culture, society and personal context.
So how do you know that your interpretations and beliefs are correct? Especially when there are equally devout people that claim to speak for God (or Gods) that contradict you? You can't all be right. And there's nothing that requires that any of your are.
Which is why your 'God said so' basis of the immorality of homosexuality is so uselessly subjective. If I don't accept that you speak for God......you've got nothing. And I don't accept that you speak for God.
So why would homosexuality be immoral barring your Appeal to Authority?
Old people having sex have often already produced children who grew to adulthood.
Yeah, but old people having sex after passing their reproductive years can't produce any children. So wouldn't any sex they have be solely for pleasure, incapable of producing children, and thus an abomination before God? Or at the very least, sexual deviancy?
At least according to the one interpretations of the one sect of the one religion of one god that you subscribe to.