How can I set up a local customer loyalty program in-store only?

[alohaexchange]

Aloha, we own a shop in Hawaii that would like to offer a discount to Locals IN STORE ONLY. We want locals to subscribe to our email list in order to receive the discount and possible part of a loyalty program if thats easy to set up as well. Is there a way we can do this in Shopify or do we need another APP to make that process smoother. We are trying to build our brand presence so locals on island can receive emails of new products that we have in store.

Again this is IN STORE ONLY. We hope to use the data and migrate it to Klayvio for our marketing emails.