Why did I have to pay postage on a returned item?

My Book was faulty on the first day I had it. After an on line chat with the WD help they decide the “drive was bad” their words. I opened a RMA and all that was very efficient, and I accept when things can go wrong. However when I printed out the return labels I was surprised to see I had to pay the postage?

Hi,

The cost of sending a drive to the returns service center for warranty service (also known as the return shipping cost) is paid by the customer. Western Digital pays for the return shipment (except for some Latin American countries). Western Digital will refuse any collect payment shipment.