I'm not sure "too stupid or indifferent" is quite fair. You have retirees who see it as a change of pace or just people who feel strongly about their civic duty (and whose companies will presumably continue to pay their salaries). That said, it's absolutely fair to say that it's far from a random slice of the population to an even greater degree that juries in general. I suspect that most (but not all) US readers on this site would try fairly hard to get out of a three month, five day a week grand jury commitment.
Grand Jury service is usually one day a week for a few months. In my case, it was 8 weeks, and we were frequently dismissed before the end of the day.
If your employer doesn't suck and pays you your normal salary, it's not a significant hardship. I've found my jury service in all instances a fascinating and educational experience the was worthwhile in the end.
It really depends on the state and county. In Worcester County in Massachusetts, they said it would be three months for typically five days a week. (My understanding is that the term of service is standard across the state but the number of days a week is a function of the typical case load in the specific county so the more urban counties require more days than the more rural ones.) I know someone who was on a grand jury in a New Hampshire county and it was (I believe) for a shorter period and only one day per week. The degree of inconvenience obviously also depends on your job. For example, if you normally travel a lot, it's going to be tougher.
