I think Veruca getting thrown down the garbage chute was a good thing in and of itself. Before her father, Rupert Salt, was thrown down the chute afterwards, he felt he had spoiled Veruca quite dreadfully.

Later, when Veruca and Mr. Salt were were leaving the factory while covered in three weeks’ worth of rotten garbage (as the incinerator was broken), Mr. Salt looked angrily at Veruca, having realized he and his wife Angina had been constantly spoiling Veruca and decided to change his ways about treating his daughter.

Plus, it was a good thing Mr. Salt showed he’d gotten some sense as he and his daughter were leaving the factory. When she said she wanted a flying glass elevator, Mr. Salt first looked up at Mr. Wonka’s flying glass elevator, and then turned back to Veruca, informing her that she would only be getting a bath that day.

Having learned what he now believes to be a good parenting lesson because of the humiliating ordeal he had suffered along with his daughter in the chocolate factory, Mr. Salt was also finally fed up with wasting both his hard-earned money and his time on his daughter and her countless copious demands, too.

I love it in the book and movie but not the stage musical.
Violet pops like a balloon in the stage musical!