To answer all the why questions.
First off, what i said does not mean i will necessarily go for a girl that wears Hijab, but if two girls are the exact same and one wears a hijab and the other doesn't, i would choose the one wearing a Hijab. Simply because the former is more compatible with my ideals.
Also if i did marry a woman that doesn't wear a Hijab, i would still try to convince her to wear one. Of course i would want her to be convinced and not wear it just to please me, as that would not serve any purpose imo.