By your reasoning, a couple incapable of conceiving a child should not have sex? Post-menopausal women, those with infertility issues, etc. have sex for a number of reasons - conceiving a child is not one of them. I suppose you might call it recreational sex. Self-serving? Why? It involves mutuality, love, concern for the other - all certainly sacramental, if by sacramental you intend a means of experiencing grace.
Um, no.
Sterility is not usually willed, and otherwise healthy, moral people who are sterile would be overjoyed if they conceived despite their apparent sterility.
Mutuality, love and concern for others which has been closed off to sharing those gifts with a third party are not fully healthy.
Besides, by your own reasoning God can overcome those situations, too. Like the couples who give up trying to conceive, adopt, then shortly thereafter become pregnant. ;)
By your reasoning, a couple incapable of conceiving a child should not have sex?Strawman argument there "Rev". Won't wash, isn't what was said. If infertile married couples have sex, sometimes we find out they aren't fully infertile. Those that are by God's Will still leave themselves open to His Will, got it?