Michael Perelman says monogamy is a societal construct that does have benefits.

Question: Is monogamy passé?

Michel Perelman :I don’t think monogamy is a silly concept; I think it’s a social construct in our society, meaning that marital stability is part of what stabilizes our society. So all societies have controlled reproduction and while science has allowed us to separate recreational sex from procreational sex, we continue to have rules about who is allowed to have sex with you because this really stems from both our religious and legal history, and essentially it stabilizes our society. All societies have rules around sexuality, these are just ours, and they vary from culture to culture, and these are our standards in our society. So I don’t think of that as silly at all.