Fashion Trends (aka I am clearly not cool)

Can someone explain fashion to me? Please?!

I've noticed a trend at shows lately. Maybe someone can explain it to me, because I just don't get it. It appears to be one of those trends that's oriented toward people too young to drink but old enough to think about boys almost as much as horses.

Neon colored sports bras under white show shirts.

I spotted this the first time with a teen at my barn. I thought it was an oopsie moment when she walked over with her neon pink bra shining through her white, cotton show shirt. It lit the whole thing up like a neon sign. Of course her show jacket is going on over top so no harm done and I just gave her some friendly harassment over it.

Another teenager with our barn had a neon blue sports bra on under her white shirt at our last show, and I stared at that. Then I saw more girls sporting this look while walking the stadium course. While I make a point of having a white or other very light color bra on under my white shirt, there seems to be a new trend toward having the brightest color bra available on under your show shirt.

Am I losing my mind, or is this an actual fashion statement like those god awful thongs with the rhinestones hanging out of everyone's pants a couple years ago? I mean, I'd hate to be unfashionable. If I need to get a lighter show shirt and a bright royal blue bra to match my show colors, I'll get right on that.

I don't get fashion.