Solution
According to IFRS 15, the consideration payable to a customer is accounted for as a reduction of the transaction price and, therefore, of revenue unless the payment to the customer is in exchange for a distinct good or service that the customer transfers to the entity. In this case, the entity does not obtain control of any rights to the customer's shelves, so the $1.5 million is not for a distinct good or service.
The customer commits to buy at least $15 million of products during the year. However, the contract also requires the entity to make a non-refundable payment of $1.5 million to the customer at the inception of the contract.
Therefore, the transaction price to be recognized by the entity is $13.5 million ($15 million - $1.5 million). The $1.5 million payment is treated as a reduction to the transaction price, as it is consideration payable to the customer.