You can't lie and say that hair does not contribute towards you thinking that a girl is attractive or not, there is absolutely no guy on the face of this earth that does not take Attractivness into account when chasing a girl.
Sure, your reason for STAYING with her may be based on personality, respect, amazing sex... blah blah blah. but the one factor that says "Hey, i wana go see if this girl has a personality, should have my respect, or enjoy my amazing sex" is because you are attracted to her, physically.
And unfortunately, by evolution and social structures, girls which do not have hair, well they generally are perceived as being less attractive.
The same logical reasoning as to why we think girls with nice hips and big breasts are generally more attractive can be used. They are better reproductive mates, nice hips are Child Bearing Hips, and Big Breasts are better Mammary glands to provide Nutrients for our growing offspring.
A girl with no hair, because of thousands of years of evolution and social conformity is seen as unattractive, because the lack of hair goes against the Social norm, meaning that she could be somehow inferior as a Reproductive mate.
Think of it like certain tribes in Africa, Indonesia, Papa New Guiney and Borneo. Perceptions of Beauty is different. Some tribes beauty is in how fat a woman is, others is how long her neck, other tribes require women to remain bald because it's what they perceive as beautiful.
But in our current Society, hair does make a difference for us. Even styles of hair. Sure the difference could be as little as a 7/10 (no hair) to 8/10 (hair) but the difference is there.
Sorry to get all Science on us, but it's my Major

tl;dr Hair Matters, it's in your Biology.