I was thinking zaps can be used as a simple way to provide loyalty card cashback. If you build a loyalty card app and integrate nostr, you simply automatically generate a keypair for each customer to set up their account. Their purchase enters the system as a note with purchase details in a particular format. A bot can extract those details and adjust inventory on the back end. Then an autozapper can provide cashback/loyalty points directly on that purchase receipt. Customers then have a full purchase history and you have data for analytics. Would be curious to hear what sorts of implementations you have done and how they have helped your workflow!