"Buttons in Ows"--One thing I've always wondered...

Maybe someone out there can answer this.

Having always been kind of lukewarm on Buttons and Mindy, I always thought it was a shame to waste the opportunity of an Animaniacs Wizard of Oz parody on them. I always thought that if they did an Oz parody, it was crying out for an all-star crossover (with, of course, Brain as the Wizard, which this short did do).

But watching it again, there was something very odd about this ep that struck me.

The Oz that they present is almost entirely depopulated! No Munchkins in Munchkinland when Buttons and Mindy land there. No one in the Emerald City except the gatekeeper--no one walking the streets or the square. And the only Scarecrow and Tin Man they meet are completely inanimate ones instead of the living creatures they're supposed to be!

It seems like even more of a missed opportunity since they could have had the characters do some gags with the Munchkins, the "real" Scarecrow and Tin Man (maybe with a short song parody or two), the Emerald City-ites, and so forth. Instead it looks...well, downright eerie, as if they're in some sort of dystopian, post-apocalyptic Oz where a plague or something has wiped nearly everyone out!

So did any of the writers/animators ever mention why they chose to do it this way? Was it something to do with the rights issues for the other Oz characters?