Cashu works as intended: give anonymous coupons to someone else.

It isn't for big sums of money. For that we already have proper anonymous crypto. It isn't to pay coffees and grocery, for that we already have zaps.

This fills a niche in the real world which isn't answered by other options. Even when the mint stops working, you won't see many people upset over it. In fact, the person running the mint is likely someone close to the customers and won't like to keep them unsatisfied for 90% of cases. It isn't perfect, but this is the real world. There are advantages to this loosen method that I think you are under-appreciating but that have a tremendous value to others.