If they did, they are foolish. Eventually those girls will find husbands with unknowable exposure. Or they may be victims of rape.
Chastity does not protect you from the behavior of others.
Folks don't plan to get into accidents but carry insurance just the same. How is this different? It's managing risk.
I can't understand parents who see a vaccination as commentary on their parenting or children's moral character. It's daft. Do they believe illness is punishment for bad behavior or are they stubbornly resistant to their child's maturation into adulthood and the additional risks that will inevitably bring?
You hit that out of the park.