The sound comes from real mechanical cash registers, whose bell rang when the drawer opened to signal a transaction and alert a shop owner. In Dutch the register and checkout are called a kassa, which is how this clip was tagged. That ringing till became the universal cha ching shorthand for money in cartoons, adverts and games. Online it spread as a short meme effect, richer than a plain ding sound effect because the drawer and coin noises complete the sale. Creators still use it whenever a price, payment or profit needs instant emphasis.