Wouldn't Gonzo technically count, considering he was a Frackle at one time?
Hard to say, Because I guess you can say that he was a Frackle from 1970 to 1975 but now he's not a Frackle anymore so.......
I don't know, Depends if your Gonzo costume looks like the first season Gonzo.
But then again, I'm sure there are some people out there who would love to be dressed as Kermit or Piggy or Fozzie or any other members of the Muppet gang for Halloween and I respect that.