True, but we read all the time about convenience store clerks getting KILLED by robbers. I think it was reasonable to be paranoid. One of the most sickening things I have seen is on the "banned from TV" video. These thugs shoot the elderly clerk in the chest because there wasn't "enough" money in the till. He cooperated fully, and we get to hear him gasp for breath and die.
But when did you hear of a family of a convienience store employee sueing the employer after a fatality? Even if such a suit made it into court, it's likely that the judgement wouldn't be particularly large. However, if an emplyee accidently killed a customer in a gun battle with a criminal over a couple of hundred dollars in the till...?