I started wearing heels when I got to my third year in secondary school, so around 13yo and by 15 had a selection ranging between 1" and 3". Even for walking long distances I'd wear a heeled boot. I just preferred the feel of them, and as I was already a fair bit taller than most girls in my school, setting myself that little bit further apart was a good thing.
I stopped living in heels when I got pregnant, figured it was probably safer, but by that time, I'd not worn flats for years and just couldn't get my feet to move properly. I was forever tripping over myself (Seriously, I looked drunk!)
I walk 40miles a week right now, half of it up hill, and in heels that absolutely cripples me, so unless I'm going off to an appointment at the other end, I always wear flats. I can't give up my heels though, and I sorely miss my 8" boots...
My daughter however has just started to make demands for heels, all the girls in her class are wearing them (as well as tight fitted shirts, tiny skirts and more make up than I've ever owned!) She isn't getting them though, no matter how many times she asks... they're only 8 ffs!