Nobody would notice the dress on Christine -- all the people would be saying "Wow, she looks fabulous!" -- which most people would be saying if she had her hair down, no makeup, and was wearing wellies, farmer's overalls, and an oversized sweatshirt. The designers want people to be saying "wow, what a dress!" especially if the female model who is wearing it could walk topless through Cincinnati without anybody paying attention.
I don't know why so many fashion designers seem to prefer female models who could be mistaken for 12 year-old boys, and I'm not sure I want to find out.