During Chapter 6, Kiryu will encounter Mr. Moneybags as part of the story who will teach him the Cash Confetti skill. This will scatter money on the street, allowing you to avoid fights more easily. You're forced to use this in order to progress the story, making this trophy unmissable. This is also related to the other achievement called Worked Hard for the Money trophy. That achievement requires to throw away 5 million yen.