The discount set creation form includes a replica of Shopify's discount creation form and, as part of that, we need the Customers scope in order to let you select specific customers or customer saved searches as prerequisites for the discount. An example would be if you wanted a discount to only apply to email subscribers or first-time purchasers.
Bulk Discount Code Generator does not collect or store any customer information, it is simply presented to you in the form when you specifically search for it and then IDs are used as parameters to Shopify's API in order to create the discount. Here's a screenshot of where it is presented in the form:
If you have any other questions related to this topic, do not hesitate to contact us and we would be happy to answer them. You can start a chat from the widget in the bottom-right corner of this page or email us at firstname.lastname@example.org and we'll get back to you as soon as possible. Thanks for your interest in our app!