It costs the consumers. Sometimes indirectly and sometimes directly. I would think that this is the primary motivation to come up with a new scheme.

Credit cards are a huge benefit to customers because of purchase protection, chargebacks, and being able to spend money before you earn it that month. The merchants pay the fees because it gets them sales they wouldn't otherwise get.

It might be one motivation, doesn’t mean it’s a good one as per the original comment if consumers don’t care.