It's about trying to maintain morality.
We all want to be proud of the citizens around us, our neighbors so to speak. Nobody wants to live in a neighborhood full of druggies or queers. It just kills property values.
Marijuana is a gateway drug. That's been proven. So by legalizing it, we are willingly removing one of the steps between our children and harder drugs.
Me? I'm not ok with that.
Homosexuality is not natural, but for whatever reason some are attracted to others of the same sex. Doesn't affect me, no big deal. But having it put out there as simply another option, as if you are weird if you don't at least experiment with it? I'm not ok with that.
Call me quaint, but it boils down to preservation of morality of our future generations.
But I don't have any hatred for you pot smoking homos.
Live and let live.