This is part of the dehumanization process. Making gays the "other" signals to the community, and the students, that gay people (or well, probably any adjacent minority category) are not worthy of any respect of decency.

And then there's bullying, violence, or even worse. And when there is bullying or violence, there is no defense against it - because why would that be a bad thing when the community says gays are bad people?

And for gay/lesbian/trans/queer kids, it is just another dagger into the self-respect and self-worth. Having grown up in this shitty milleu in Cobb County, I can say it takes many years of personal work and therapy to purge oneself of internalized hatred.