And also, let's not kid ourselves...no one cared about the AE86 much before Initial D gave it a nostalgic explosion of fame. And even today, you're hard pressed to find a true AE86 without a shitton of mods done to it.
http://youtu.be/di_X8IQLlAw?t=11m30s
http://youtu.be/G4jxGvUZKEw
The AE86 has been well liked since it was released, i.e. the late 80's early 90's. The manga was based on it's cult following, not the other way around.
Also, I see quite a few AE86es on craigslist, more often than not with few to no mods. Some are asking crazy prices because of their popularity, but others are just old and beat.