@po8crg @goatsarah I think that Chicago pizza is at least similar enough to unqualified pizza to bear the _qualified_ name. It's perfectly standard for an X Y to be _somewhat_ different from the prototypical Y, and I don't think that chicago pizza exceeds that level of difference, unless "pizza" is defined _particularly_ narrowly.
(disclaimer, it's been many years since I've eaten a Chicago pizza. It didn't make a massive impression on me, gastronomically-speaking.)