HOW DID RAW denim get fetishized to the point of absurdity in the past couple of decades? What started as an innocuous trend for classic jeans became a persistent, profitable craze that spawned a religion. Denim zealots chronicled the elaborate processes they used to break in their jeans in YouTube videos, on blogs and with fanatical Instagram accounts. For the better part of the 2000s, this was the modish approach to denim: Buy jeans in unprocessed dark indigo the consistency of military-grade tent canvas, and don’t even think about bending your legs for six to eight months. Those of us who questioned the labor-intensiveness...