Speaking from my own (ex-Christian) upbringing, I got only the vaguest references to people being gay as a child/teen except that they were all sinners. I certainly couldn't have held a rational conversation about it because, aside from references inside the church I didn't know any gay people (maybe I did, who could know).
It wasn't until I reached adulthood and left that community behind that I began to realize the way LGBTQ* people are and were demonized within certain christian circles.
The argument that marriage is solely for procreation, and/or the property of religions doesn't really hold water. Christians I have come across, seem to think they invented marriage, which is just not even close to historically accurate.
As to procreation only, this is fraught with the way laws treat things like next of kin, power of attorney and tax benefits. None of those things, have anything to do with procreation and yet they're a big part of marriage.
On the positive side @drewbug01, over the course of 15 years I have gone from incredibly uncomfortable with the whole thing (because of upbringing), to some of my best friends being from those communities. There is progress, and with any luck there will continue to be progress.
