I think a lot of these fashions you mentioned are just that, CURRENT TRENDS. Kids all want to be alike and those that should be grown by now still want to appear young.
When I was in my teens and 20's I wore all the latest syles, hip huggers, tank tops or tube tops, micro mini's, hot pants etc. It was the style. I'm sure my mother had more than a few days of rolling her eyes at me but she didn't take me to WDW in those early teen years, we couldn't afford it. If she had, I would've worn all of the above because that's what we wore.
Styles will change and these teens will too, the adults trying to look 18 are no different that those in the 70's wearing the 60's beehive hairdo, blue eyeshadow and mascara that was 3 inches thick. Some just never want to grow up.
I try to remain stylish but also look nice, current and almost my age

.
I bought 3 bathing suits yesterday, 2 one pice and one 2 piece, shame on me a woman of 50! But I looked pretty darn good in it - Don't worry, I've never worn a b-suit to the parks and don't intend on starting now!
denise