... I have hair that long. ^_^; I know not everyone has that kind of hair-length, but for me, hair that long isn't unrealistic. As a result, a lot of my characters have long hair!
To clarify my point to those who might have misunderstood; I'm not saying that wearing sensible boots to go fight a dragon is equal to coding a character as virginal and virtuous. What I'm talking about is pretty well exemplified in this image of Mary Marvel:
These women are both the same character; on the left is Mary Marvel when she is morally good. She's wearing all white and gold (white being culturally associated with innocence and virginity), with loose-fit sleeves, more flowing, cotton-y fabric and a more child-like cut to her clothing. On the right is Mary Marvel after she has been corrupted and gone evil; her outfit is now mainly black, and seems to be made of latex or shiny leather, she's got garters, fishnet stockings and shiny leather boots - all of which are often associated with sex and sexualised clothing. The lower half of her outfit is basically sexy lingerie, and the top half isn't much better.
So, this costume change equates moral goodness with child-like innocence and virginal visual cues, and moral evil with sexy lingerie and sexual availability.
This is the most obvious example I can find on short notice, but it's certainly not the only one - it's quite common. I'm really not fond of it.