Bradbury describes the opening scene of the Hadley's home in great detail to show that EVERYTHING is made with tech and AI; not even the toothbrush is "manual."
The children become obsessed with the house as it acts more like the children's parents then their real parents. The technology doesn't care about the people and just does as it's told. The children become attached and when threatened tell the house to hurt the parents.
The threat is made when the technology shows the mental state of the children and how they use the tech to simulate death. When the parents go to turn the house off the children freak out on the parents.
The children react poorly to this and try to keep the house on no matter what it takes using the tech to get rid of the parents.
The story has "ended" with the parents being cornered by animatronic lions, implying they were eaten by the technology that made them.
The take away from this story is to not let technology absolve us, as humans.