That's a common straw man, and it wasn't what wideawake was saying at all. Even with infertile couples, sexual intercourse still is potentially procreative, because infertility is sometimes overcome.
Yes, a pink unicorn might gallop by and miraculously put a fetus into a woman's non-existent uterus. But I think that is a lot less likely than a fertile woman getting pregnant despite use of The Pill.
When I last checked, I understood that even the Roman Catholic Church recognized that sex without procreation is still a valid use of the equipment, as it can bring couples together emotionally.
But perhaps I misunderstood.