Several years ago, an AA Executive Platinum desk reservation agent whom I knew well told me about an AA customer who'd book flights to his domestic U.S. destination followed by a refundable ticket to some overseas location so he'd get lounge access on that trip. He'd then refund the overseas part. Everyone at AA knew exactly what he was doing, but he was so profitable to the airline (he flew about 150,000 miles per year, most of it at full Y or paid F) that they let him keep doing it and keep thinking he was getting away with something.