Of course. But like all agendas, the homosexaul agenda is all about benefit in one way or another. The sure way to stop at least a part of it is to get government out of marriage.
In a way, it's much like our problem with illegal immigration. If living here weren't a bonanza of freebies, you'd find that we wouldn't have much of a problem.
I think most of us can agree that we don't care what homosexuals do in private. So perhaps that should be our push. To move it out of the public sphere.
The homosexual agenda is much more than benefits, they themselves admit that.
It is about changing society, they have admitted it over and over again, and Libertarianism is cheerfully assisting them.