I would recommend you attend and perform this duty.
"A jury of your peers" is every citizens right and you are a "peer". Sure the pay is not great and the case may last several weeks or months but I think it's one of the most interesting and rewarding experiences an American will ever have. You will certainly walk away with much greater insight on how our justice system operates, and that alone is well worth the time in my opinion.
Food or Snacks? Not sure, it might be a good idea to contact the court for related info.
And try to be as honest as possible when the Attorney's ask you a question during the "Impaneling" process.