Yes, there's that. There's a lot of Jewish theory of "you've got to remember that this was written 3,000 years ago."
A lot of religious law was made to protect people from dangers that they didn't understand (see dietary laws because of not understanding bacteria). The "Man shall not lie with man as he lies with woman" is tucked alongside all the incest and many adultery laws. If you think about it in terms of sexual diseases (Syphilis is one of the oldest diseases in the world, with a theory that it existed both in Europe and Pre-Colombian America, to give you an idea of its age) it makes a lot of sense. A married man and woman would only be allowed to sleep with each other. Adultery had the chance of bringing in disease into the relationship. Homosexual sex was similar to adultery because two men would not be bound by marriage and therefore not be committed to only have sex with each other and could also bring in disease into a married relationship. In Judaism everyone was supposed to get married, NOT for the reason "to be fruitful and multiply" (though they certainly tried) but for companionship. Otherwise there probably would have been laws about men divorcing women who weren't able to conceive.
See? This is a much better argument, appealing to Jewish culture and tradition. I would note, however, that it makes perfect sense that there wouldn't need to be cultural directives about reproducing, because what kind of latex or chemically engineered birth control did they have available at the time? Kids simply happened in marriages with couples able to conceive; one could make a strong argument asserting that there would be no need for God to instruct about that (though I'd note that
he did anyway, quite clearly) because sex and babies are inextricably linked.
In the same vein, Christians who are pro-homosexual marriage relationships in the church cannot make their argument without also disowning the notions of what constitutes God's instructions for families, i.e. thinking that it's okay to get married with the intention of never reproducing (the teachings exclude those who are physically unable, of course). This argument seems logical, but requires disowning major themes in Christian teaching, which I almost never see happening.
Christianity revolves around a life of
practicing the fruits of the spirit: self-control, kindness, gentleness, etc. and these are woven throughout the Bible teachings in direct relation to intergenerational interaction. You can't be godly or search after holiness apart from the spirit*; kids require parents to turn their lives upside down and reorder their priorities from being self-involved to other-focused. These concepts are core to the development of the Christian as spelled out throughout the entire religion; it's supposed to help us fulfill our roles bringing the kingdom here on earth as it is in heaven (Lord's Prayer reference).
That's why Paul says it's easier to not get married, because to do so requires one to reorder one's life around others both younger and older, taking an active role in the community, whereas he as a bachelor does not hold responsibilities to anyone but the church.
It's fundamental. Yes, homosexual relationships could still engage in intergenerational family relationships, but they're cutting out a lot of the Bible teachings, using a surgeon's knife to make it work for that way of living. There's a lot of references in the Bible about what is the good and right way to live one's life as a family member, and they all revolve around heterosexual marriage relationships. Just as it's against teachings for me as a non-married individual to engage in any sexual activity, it's a sin for anyone outside of a heterosexual marriage relationship to engage in sexual activity. Key word: activity.
*
RECAP
1. You can't be godly apart from the Spirit; you're just not at that level, and not that kind of good.
2. As a matter of our nature, we are hell-bent on getting what we desire. Even the best side of you gets twisted by this inner drive.
3. God has a very different way, and wants you to follow it. Since you can't, the Spirit grows you up, cleans you up, and makes good ('fruit') come from you, in the manner of Jesus Christ.
4. Where there are 'the fruit of the Spirit', the Spirit is at work. You can put your trust in this truth.
5. Each person in the Spirit has the fruit differently, and each fruit has a different shape in each person -- but all the spiritual fruits will show themselves in each Christian as he or she goes deeper into their walk with the Spirit.
-from the link