cohan买了双鞋20%of+rakutan还有18%的rebate,算下来80不到

https://www.colehaan.com/grandpro-breakaway-sneaker/196414418057.html?cto_pld=GUm58y-FAQAy6Kd7NDdyGw&utm_campaign=SimiliarSiteVisitorsnew&utm_content=0&utm_id=387839&utm_medium=display&utm_source=criteo
老大看了这鞋驺眉头哈哈哈哈哈哈，就想买个有点男人气的鞋，配牛仔裤或者裙子都可以

为啥我只有8%rebate？