Not really sure, especially considering the existence of the Wii U Pro controller, which is even more comfortable than the GameCube controller.

I never thought of that, but it makes total sense.

The pro controller is better. Unfortunately, you can't wire it, which is stupid.

Hey look... the Wii U really IS GameCube 2.0!

Now Nintendo just need to release Melee on the VC to get people warmed up.

It's the perfect controller for Smash. Also it's pretty neat that we'll be able to use a controller from 2 generations ago.

Because the tourney scene has been using it for over a decade as a result of the Wii having less than stellar controllers for Smash Bros.

Had a good laugh at some of these comments though.

Isn't it also the only wired controller you can use with the Wii U too? Unless there's some 3rd party wired controller bu I haven't seen one.

For pro players, any lag is too much lag.

The answer to the OP's question is:

Because a bunch of whiny tourney nerds who think THEY are the only fans that matter when it comes to Smash, complained to the heavens that this new SB was going to be HORRIBLE, because they couldn't cling to their beloved GC controllers, because don't you know, Melee is the best game ever created.

And as we all know, the squeaky wheel does sometimes get the grease. SO much so that Sakurai is even bending over backwards to put a Tourney-Tard mode in the new game, with No Items + Final Destination being the rule. I'm surprised the mode didn't also include Fox Only.

It's the best controller eva!!

It's also meant for Smash. Playing 64, Melee and Brawl on the Wii is best with a GC controller.