Miss Poogy and Foozie are the only Moopets that talk. I saw the movie last night. They don't even mention Miss Poogy's name. No one knew her (?) name.
That's weird, considering her name is widely sourced. I find it weird when a major character in a movie has a proper name that's never mentioned on-screen. I used to wonder what the point of giving characters non-descriptive names was if they weren't going to be mentioned (first I realised it's probably better for character merchandise... After all, what if all Marvin the Martian merchandise was labled "Martian"? Then I realised that when writing scripts the writers probably don't think in advance as to whether there'd be opportunities for all named characters to be mentioned by name, no "if this character has a name we have to mention it in the film" mindset...).
I might have explained that badly.... It's more like when there's a scene focusing on the band and Zoot is there but doesn't have a line, the chances are 99.9% that it's Dave under there. Because it's his character. I think it's that kind of thing. Sully and Richard Hunt might be a better example.
I think I've talked about this in a thread long ago, but I find it interesting that many characters who either rarely or never talk have had consistient performers (Lips, Bruno, Barkley, Foo-Foo, Sully, Gaffer, not sure if Zoot should be counted here), yet quite a few minor characters who get lots of dialogue in their appearances (Doglion, Boppity, Betty Lou in the 1970s and 1980s, etc.) are always performed by whoever's on set to perform them.
EDIT: I started my own thread regarding oddities in the credits:
http://www.muppetcentral.com/forum/threads/characters-in-the-credits.49059/ But I wonder if the Janice Moopet might have been primarily performed by one of the "additonal Muppet performers". Additional Muppet performers sometimes get speaking roles who don't get noted in the credits.