Community is key to long term survival. Some members of society carry one load, others carry another. Mrs. Harrison has worked with her community and they know what she has and there are probably members who have much of the same but maybe use Mrs. Harrison's grinder. These others are probably set up to handle interlopers so that those who shun guns don't need to deal with it, nothing is said about teh preps of others in her community. Just because Kathy Harris doesn't own a gun doesn't mean she is an easy target.

Then again, misdirection is always a possibility. It's hard for me to imagine a group that has plans to be very self-sufficient in a crisis not being prepared to deal with the wolves in society at large.