The alphabetsexual culture is a leisure society feature. In a post-apocalypse survival scene, we would go back to boys and girls and their necessary roles of hard work and bearing children. Anyone not doing their part would be offered to the wolves.
Yep, people have way too much time on their hands, and need to do things just to alleviate the boredom, so they engage their brains by coming up with all these new insane ideas.