Orson Scott Card is a Mormon, a religion with a rich history of bigamy. I'm wondering where he got his morals? Judging from the Titles of some of Orson Card's books, he hardly seems like a philosopher I'd whose ways I'd chose to follow. "How To Write Science Fiction and Fantasy" ???
What's bigamy got to do with supporting your children? A plural marriage in which the father is living with the mothers of his children, and supporting those children, is likely a whole lot better than a "family" with no father present, and perhaps one not even supporting younger children. To the early Mormans, there was nothing immoral about a man with more than one wife, as long as he could support the wives he had and their children.
That said, one woman is bother enough at times, although still better than no woman.