I take it these are FBM orders? Answer is who knows. We generally now see in the main the prepaid return labels provided (do note that depending on the return reason, the customer may get the cost of the label deducted from their refund).

We would sometimes have some orders we have to approve, where its up to us then to decided what we supply. Normally, these are items amazon deems hazmat (ie batteries or products containing liquids or gases) but generally speaking - I've not seen an order where the customer has just been supplied a return address label for a while.