Why not?
The forces pushing gay marriage are the same ones pushing the sexualization of minors, easy divorce, and every other assault on the traditional family.
Both gay “marriage” and the promotion of out of wedlock births are just different facets of the same policy:
devalue, undefine, and destroy the traditional family.
Orwell touched on this in 1984 - personal relationships were forbidden because they took away loyalty from Big Brother.