Welcome to the community forum and thanks for posting.
I understand your concern about adding a reward card. The physical gift card/ prepaid gifts cards can be linked as a payment method and be used for redemption during checkout just like any other credit or debit card. To redeem a Digital gift card, please check this help center article. You can also exchange a gift card for a PayPal balance, here's the helpful link. If you need any account-related concerns, please reach to our customer support team via the contact options on our website.
I hope this helps,
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