Trey Anastasio wins Halloween. It’s over. We can all go home now. Walking on stage at The Wiltern in Los Angeles, Anastasio revealed his Halloween costume: His very own meme. A while back we told you about the latest craze on jamband Twitter, a meme-able moment where the guitarist was caught pondering his smoothie options at a New York deli while holding a bag of oranges or some sort of…