> Men want to know that the children they raise are their own.
You realize that the number (>0) of prior sexual partners has nothing to do with the parentage of one's children, right? You can marry a virgin and still be a cuckold; or you can marry a prostitute and sire a large family.
Of course. “Body count” is a poor proxy for fidelity. That doesn’t mean it hasn’t historically been used for that purpose.