Answer: Because they are exploiting she and her step-mother.
Step-by-step explanation:
Gretel is the titular character in the short story, ''Gretel'' by Garrison Keillor. Gretel believes that her drunk of a father is exploiting both she and her stepmother and so dislikes him.
Gretel is also a writer but her brother covets her profits from publishing a book and wants the lion share for himself whilst giving her a meagre amount. The lawyer ensures that this happens by putting Gretel under a spell that made her sign a contract that gave her brother his wish. This makes her hate both her brother and the lawyer.