The offers at, Inc.'s (AMZN) Prime service never seem to end. The Seattle-based company introduced yet another program yesterday to garner more users for the service, which already includes a slew of offerings from expedited delivery and free shipping to discounts and video streaming services. The new initiative is called Prime Reload and offers Prime members a discount on site purchases made using debit cards.

Both users and Amazon stand to gain from the use of debit cards as opposed to credit cards. For Amazon, the move translates into savings on credit card processing fees, while its Prime customers can avoid costly interest rate payments by debiting their bank accounts directly. Amazon has offered to refund users 2 percent of the total bill as a bonus for debit card use. (See also: Credit vs. Debit Cards: Which Is Better?)

The e-commerce behemoth has been firing on all cylinders this year in its drive to enlist customers for its Prime service. Last week, it rolled out discounted Prime rates to target low-income households. In April, the company launched Amazon Cash, a service that enables purchases for people without access to banks or financial services. In January, it introduced the Amazon Prime store card with Visa Inc. (V). The card offers a slate of discounts on Amazon purchases and at restaurants, gas stations and drugstores, among other places.  (See also: Amazon Prime Becoming Popular in Low-Income Households.)

The value proposition of Prime customers to Amazon's bottom line is clear. According to research, the average Prime customer spends twice as much as a non-Prime customer on the company's website. A Prime membership also helps the company lock customers to its platform. In an SEC filing earlier this year, Amazon disclosed that it had earned $6.4 billion as Prime revenue in 2016. Research firm Consumer Intelligence Partners estimates that Amazon has 80 million Prime members. (See also: Who Are Amazon's Main Competitors?)


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