I think so. From what you write is that when you want to purchase an item you want to look if you can submit a rebate voucher or gift card. More importantly the seller does not discount the product but decides on the request to which you add a rebate voucher or gift card.
- The gift cards nor the rebate vouchers have any value until you actually purchase an item and render these.
- You pay the full price and submit a rebate voucher or gift card
- The seller considers the request and transfers the rebate to your account at a later date.
So follow the post by @Tut at Rebate from Supplier