Bart wins a radio station phone-in and is given a binary choice: $10,000 in cash or a full grown African elephant.
Bart chooses the elephant.
So they try to negotiate (‘We think we know how your mind works, Bart’) and offer other alternatives which are equally stupid, but less costly and destructive.
Eventually, to keep their jobs, the radio people crumple and get Bart a fully grown African elephant.
“$58 and all of it profit!” declares a delighted Homer, “I’m the smartest businessman in the world!”
“Stampy’s food bill today was $300” replies Marge.
So the Simpsons end up with no elephant, just bills for hundreds of thousands of dollars, having alienated their neighbours and trashed the entire neighbourhood.