Oh, wait, that's because a lot of fanfic writers are probably high school students.
It's still strange. I mean, for FFVIII it makes sense, in a way, but... for things like FFX and FFVII it hurts my head.
I suppose somewhere out there on the net there's probably a BORG COLLECTIVE high school, with Seven of Nine flirting with all the boys, or perhaps a Pirates of the Carribbean High with Sparrow picking on the class nerd Billy, or...
*shakes head to clear it*
On the other hand, cupcakemonster wrote a gangsters Spira that I adore, even though I usually avoid that genre. So you just never know.