Question: Is there any reason why Miss Hannigan hates the orphans?
Answer: It's not hatred as much as it is resentment. Miss Hannigan is unhappy with her life and blames having to work in an orphanage for her woes.
Question: Whatever happened to Miss Hannigan? (04:59:34 - 04:59:59)
Answer: In the original play, she went to jail. At the end of the movie, she was riding an elephant. Mostly likely because she wanted to stop her brother Rooster from hurting Annie, she was given a light sentence: probation with community service.
Answer: Think of the circumstances. A group of obvious orphans shows up at your house at night, saying they are friends of Annie. Warbucks knows how far the orphanage is from his home since he went there earlier. Annie believed her parents were already dead, as so many people showed up claiming to be them but didn't have the locket. Annie was very hesitant and unreceptive toward the ones who showed up to bring her home. Warbucks also caught a bad vibe from the fake parents when it came to giving them the reward check. It's not hard to believe that he would instantly realise that he was scammed and Annie is in trouble.