I agree that having little girls get their hair, nails, and makeup done sends some disturbing messages.
I want my little girl to
-use her imagination to engage in creative play,
-use her brains to solve puzzles,
-use her limbs to run, jump, climb, and do somersaults,
-use her eyes to look at picture books and work on developing sight vocabulary,
-develop her affection for others to build friendships,
-maintain her sense of excitement and awe at all the cool new experiences life has to offer,
etc.
I want my daughter to be so busy enjoying life that sitting passively and having her hair, nails, and makeup done would seem boring.
Primping for preschoolers (or elementary school kids) seems wrong to me. I don't like the element of pre-mature sexualization, but I also don't want little girls taught that self-beautification is as fun (or more fun) than playing. Reserving time at Disneyworld to get make-up put on strikes me as a way of saying "Even in this really special place with hundreds of things to do, grown-up beauty rituals are important." To each his or her own, but I'd rather take my kid swimming.
By the way, I don't think either nail polish or make-up are inherently bad. If my kid were in "The Nutcracker," I would certainly let her wear make-up. If she were at a friend's house and the Mom painted her nails, I would be fine with that. But setting aside time while at DISNEYWORLD to get adult beauty products put on my already beautiful preschooler? I can't see it.