Symbolism, Imagery, Allegory
The "three little monkeys in a cage that were hugging each other like crazy" are a symbol of Lorraine, John, and Mr. Pignati's friendship. Thinking of how they must look as they roller-skate out of Beekman's, Lorraine makes this analogy herself:
We must have looked just like three monkeys. The Pigman, John, and me—three funny little monkeys. (8)