They are hoping to be the last ones killed by the Muslims that is why.
The Quran states
Men are the maintainers of women because Allah has made some of them to excel others and because they spend out of their property; the good women are therefore obedient, guarding the unseen as Allah has guarded; and (as to) those on whose part you fear desertion [committing a religious sin], admonish them, and leave them alone in the sleeping-places and beat them; then if they obey you, do not seek a way against them.
So the man is superior. The woman is obedient and can be beaten. Thats nice.
Theres more: If the woman is not Muslim the Muslim male has the right to own them as slaves. They can be captured as spoils of war (jihad). They can be sold without their consent. Can be kept as sex slaves and any children born to them will be Muslim. Weve seen this happening recently in Northern Iraq. The ISIS warriors captured Christian and Yazidi women and sold them as sex slaves.