Final answer:
The promotion demonstrated by Rakuten providing members with money back when ordering online at certain sites is known as a cashback reward program.
Step-by-step explanation:
Rakuten's cashback program is a promotional strategy designed to encourage customer loyalty by providing monetary incentives for purchases made through its service. This form of promotion is an effective marketing strategy in the goods market, similar to the concept of a money-back guarantee, which serves as a promise of quality and encourages consumers to make purchases.
However, the cashback reward differs in that it provides a monetary incentive after the purchase, rather than a reassurance of quality beforehand. It encourages repeat business and customer loyalty by offering a tangible benefit for shopping through their service.