Why not? First of all, there are so many people that love Grateful Dead and think back to the good times when they were the biggest band around, and traveled to see the jam in concerts. Also, it seems to me like many famous people from all places are coming out this time around, and supporting candidates in this election. It speaks for how important this election is and how ready the public (celebrities and non-celebrities) is for a significant change in America. I haven't heard of Grateful Dead or many others like Oprah supporting presidential candidates in the past, and it makes the candidates look very good when they are supported by these people. Way to go for Obama, and way to go for the members of Grateful Dead to care.