As I was soon to learn, Parrotheads are Jimmy Buffet fans but to say they're just that is hugely limiting. Their slogan is "Party with a Purpose" and man do they deliver on both promises. These guys are always finding ways to help organizations and have fun during the process and giving to charitable causes is a requirement. You can't even start a chapter without making that commitment. According to Wikipedia, they collectively raised $2.2 million for charities in 2005 and devoted thousands of volunteer hours, too.
Even though they don't have a Parrothead Club for the Homeless, I consider myself a lifelong member and can't wait to meet more of them along our travels.