When you read an NFC pass, you are simply getting the data stored in the payload. This is restricted to a relatively small amount of just 64 characters. What happens next is rarely the same between two implementations. The payload could be a loyalty card number, a coupon or offer SKU, or a sporting event ticket or season pass.

It is up to your implementation to know what to do with the payload, and how (if necessary) to respond after the NFC pass has been read. For example, with a coupon, you may wish to void the coupon after it has been used, whereas for loyalty, you may want to use the number to apply points and perhaps offer some coupons based on what has just been purchased.