如题：抽奖商品0元订单返回的priceInfo结构中为何没有商家优惠金额或者平台优惠金额？

样例单号：3723392162795754496

priceInfo报文：

        "price_info": {
            "freight": 0,
            "order_price": 0,
            "product_price": 6900,
            "finder_discounted_price": 0,
            "merchant_receieve_price": 0,
            "merchant_discounted_price": 0
        }