Cashu is awesome.
David Chaum would be pleased to see what you're done.
I couldn't find it, but he made a cartoon explanation of an IRL scratch off card that could be used as physical ecash. It had multiple denominations on a single card, and you scratch off a few QR codes in different denominations to reveal the payment amounts for scanning by the merchant.
Maybe you could team up with Madex or another artist to design a promotional scratch off card for conferences or IRL orange pilling kits.