Hipsters and stoners converge at Checkpoint Charlie’s on this muggy Friday evening. The smell of stale beer drifts through the air and the next band up is the Zydepunks. The front man is shirtless, a tall woman in a red dress is on the left side of the stage, and your average-joe bassist is in the rear puffing on cigarettes next to the drummer. Something is different here, though. The members of this self-proclaimed punk band are all holding accordions and fiddles. There isn’t an electric gui...