The male, celibate Roman Catholic hierarchy has a simple view of sex. The only way it can be "justified" is procreation. Augustine's view that any married couple who has intercourse without the explicit intention of procreating is sinning still informs the magisterial view of sex. Of course, this sometimes leads to remarkable view, such as the possibly apocryphal story that some idiotic moral theologian said that masturbation is worse than rape, since there is a possibility that rape can result in procreation.

The unmarried men who come up with these teachings don't have a clue about the place of sex in marriage, and don't seem to want to learn. They have a "theory" about sex, and don't let reality bother it.