She fed them poison and gave them pain.

She did! I saw it on the DVD without pausing or freeze-framing. It is as clear as day!

After Babette moves in and gets her "cooking lesson" from one of the sisters, she is instructed how to make gruel with pain. I think that word roughly translates into "bread" in English. So that accounts for the pain.

She is also told to slice the poison thinly and put it in the pot. I think the French spell it with the double-s poisson but it is featured prominently in the early scenes.

Not a great diet with no fresh fruits or vegetables. I am surprised that they don't have more health problems with the missing vitamin components!

Actually I was puzzled about the change of attitude of the townspeople. I assume this was the first time they got tipsy from wine. What about the next day....after the hangovers...wouldn't they go back to the snarling curmudgeons they were at the beginning? Wouldn't they be dissatisfied with their daily fare after such a treat? Babette woke something in them that (maybe) should have been left alone.

"When you throw dirt, you lose ground" --old proverb