Yeah, it’s hypocritical. Tradition and religion are good tools to control people, but they sometimes conflict with the goal of exploiting those lower on the totem pole. A sufficiently indoctrinated populace won’t resist (much) though. Especially when we are distracted by things like “ermagerd, look at those less fortunate than you!” or “look, she was born a woman but wants a dick, isn’t that TERRIBLE???” or “celebrity did that yesterday, isn’t it despicable???”.
Marriage is a type of ethical monogamy.