These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Fridge Brilliance: Once it's established by the Tiffany Aching books that a witch cannot work her magic purely for her own benefit without succumbing to bad karma and/or cackling, Lilith's conduct makes more sense: by claiming she's giving others a "happy ending", she rationalizes her own power-mongering as being for somebody else's benefit, not her own. They don't get a say in the matter.
Another one; during the parody of The Wizard of Oz, Lilith tries to kill Nanny Ogg by dropping a house on her. Nanny survives, despite the fact that dropping a house on a witch is supposed to kill them, at least according to Lilith. This is actually another case of Lilith being Wrong Genre Savvy; the house is supposed to kill the wicked witch...and Nanny Ogg is a good witch. Lilith, of course, doesn't realize that she herself is the actual bad witch.
Hilarious in Hindsight: The idea of a dictatorship presented as a warped version of Disney World and an evil fairy godmother predicts the plots of the first two Shrek films (although the first one has been around for a while), and now Disney's actually made a movie set in New Orleans.
Featuring a Baron Samedi look-alike and a voodoo witch who sees the future in her gumbo pot.
And the Samedi character kills another character (who is also a small animal) simply by stepping on him.
Moral Event Horizon: Lily crosses it when she transforms the footmen into beetles and then treads on them—in-universe trope, as this seriously shocks the witches, who follow Thou Shalt Not Kill.