If it's a trial of more than a few days or a week, those people do get shut out, but they can usually manage for a short trial. I have had numerous long trials in my career and those jurors are definitely shut out. In fact, we will sometimes call for a special pool of 500 jurors in order to sit a panel of eight, with three alternates; and we're lucky to sometimes seat a panel out of those who were summoned because only about 200 show up.
