It's wrong to wish harm on another person.
Marcy sees Al stealing from the local grocery store.
Marcy wants to alert Al that she saw him do a misdeed.
Marcy tells Al that she saw him steal, and she hopes he puts the food back.
Marcy tells Al that she saw him steal and that she hopes he dies.
Al tells Marcy that he's hungry but that theft is indeed below him and feels good about returning the stolen food.
Al, who is stealing because he's hungry is appalled that someone would wish death upon him for a relatively minor crime.