Another thing which struck me - I'm not sure if this is true of Dante's Inferno, but in Niven and Pournelle's modern adaptation, they take the opportunity to pillory real people they dislike. The Chocolate Factory is rather like a candy-coloured Inferno, with various punishments assigned to various sins. I wonder if Dahl was also taking the opportunity for revenge on children's behaviour that he couldn't stand - surely chewing gum isn't much of a "sin", compared to Augustus Gloop's gluttony or Veruca Salt's spoiltness.