For global catastrophic risks the costs of food storage become impractical for most of the population  and for some such catastrophes conventional agriculture would not function due to the loss of a large fraction of sunlight (e.g. during nuclear winter or a supervolcano). In such situations, alternative food is necessary, which is converting natural gas and wood fiber to human edible food.
Articles on the subject appeared in small-distribution libertarian publications such as The Innovator and Atlantis Quarterly. It was during this period that Robert D. Kephart began publishing Inflation Survival Letter (later renamed Personal Finance). For several years the newsletter included a continuing section on personal preparedness written by Stephens. It promoted expensive seminars around the US on similar cautionary topics. Stephens participated, along with James McKeever and other defensive investing, "hard money" advocates.
Say you're at work and a terrorist attack occurs. Roads are closed to any and all traffic but you only want to get home - even if that means walking. You may not want to grab your full on family pack in the car or you may not even be able to get to it. But you just want a light kit to get you through. How far is it to get home from wherever you may be? This get home kit should provide for 1-3 nights of traveling on foot till you make it home.