Amount or number?

Just to prove how crotchety I am, here's another grammar-and-usage pet peeve: the way many people, including radio journalists, confuse "amount" and "number." Do any of the following make you shudder?

A. "There was a good amount of people at the wedding."
B. "I've never seen such a large number of ducks on that pond before."
C. "The amount of natural disasters happening around the world is really frightening."

I hope you selected (A) and (C). "Amount" refers to continuous quantities, like water or oil or money or happiness. For discontinuous, countable quantities, use "number." For example, you can eat a large amount of cake but a large number of cupcakes. You only need a small amount of shoe polish to polish a small number of shoes.