NO society has every permitted homosexual marriage, or even treated homosexuality as equally acceptable to heterosexuality. Men have always been expected to marry women and sire children. Some societies (such as the Muslims) condone homosexual activity, but never the homosexual lifestyle. In other words, homosexuality may be acceptable as a side dish, but never as the main course.
"No society"? The Classical Greeks certainly encouraged homosexuality. In fact, they felt heterosexuality should be reserved solely for procreation.