The Grateful Dead and conspicuous consumption are terms that don’t pair well, but the homemade tie-dyed culture found at Deadhead tailgates has officially gone high-fashion. While Prada sells $2,480 tie-dyed dresses on Net-a-Porter, companies that got their start selling bootleg T-shirts outside those Dead shows have quickly found themselves participating in GQ spreads. Online Ceramics, often referred to as the Supreme of Shakedown Street, sells out of its $90 shirts within minutes of posting them on its charmingly rustic website. ­