How about this?
If Star Trek fans are called Trekkies, why aren't Star Wars fans called Warzies? Or...or anything for that matter.
And what do you call Scooby-Doo fans? Scooby-Doobies? Dooheads? How come Bronies, Trekkies, and Deadheads are the only fan base that has a nickname? And on the subject of Hasbro, do you call G.I. Joe fans Joes?
There's actually a lot more fan nicknames than you may realize, it's just that some of them aren't official, or set in stone, though some are.
For example:
Muppet fans are unofficially officially known as Muppet Freaks (which originated here of all places).
Alvin and The Chipmunk fans are unofficially known as Chipaholics.
M*A*S*H fans are unofficially known as M*A*S*Hers.
Kathy Greenwood fans tried coining the nickname Greenwood Gang.
Greg Proops refers to his fans as Ocelots.
Sid & Marty Krofft fans have an official nickname known as Kroffters.
Katy Perry fans are officially known as Katy Kats.
Lady Gaga fans are officially known as Monsters.
Fan girls who are obsessive compulsive about anime are known as Otakus.
Kardashian fans are known as menaces to society.
Those are just a few that I know of.