As mentioned by another, a lot of it really is compensation. Most jobs won't pay your missed days for jury service. They can't fire you, no, but they also dont have to pay you. If you have kids, live paycheck to paycheck, then get a letter from the government saying you will be needed for an unspecified amount of days, possibly weeks, and won't get paid for it, it doesn't seem like much of an opportunity. Better have those sick days saved up, cause if not, you may not make rent.

Luclily they usually pull a large pool of people so that is sometimes not an issue. My last jury summons, I told the judge that I wasn't paid for being there and the loss of income would cause me financial hardship. "Thank you sir, you're excused."

Employers respect jury service only as far as the law requires them to. They do not respect it enough to make service economically viable for their employees.