Of all the supplies they suggest you legally or illegally procure, epinephrine sounds like the biggest stretch. We don't want to burst anyone's bubble, but if you suffer from life-threatening allergic reactions and really think you're going to survive limited food sources and practically nonexistent medical care, we've got a mint-condition fallout shelter to sell you.
Learn how to use it – What good is a compass if you don’t know how to use it? Not much. How about your Tenacious Tape? Or your GPS locator, or multitool? It’s great to head out into the wilderness with all the appropriate survival gear but if you don’t know how to use it when the time comes it will be as useless as the “g” in “lasagna”. Once you’ve decided what you need and have purchased everything take the time to familiarize yourself with what you have and how it works. Take the GPS locator out into your local state park and practice with it. Practice starting a fire with your emergency fire starter. Buy some extra Tenacious Tape and a cheap raincoat and practice cutting it up and making repairs. Take your survival knife out on a short hike and see what its practical limitations are when it comes to cutting wood etc. You might need a larger one or one with a longer serrated edge. The bottom line is this: make sure you know how to use the survival gear you have before you leave civilization behind and head into the woods.
Each type you listed (save a couple) will have its uses in a community (group if you will), generally having a small trusted group with each having several skills in the various fields (prepper, homesteader, and survivalist) I believe would be an effective team, though as each group works together would it not be best to ensure that each has overlapping skills in case of injury, death, or other reasoning they can not fulfill their duties?
In addition, the kits may contain typical individual "survival kit" items, such as nylon tarps, extra clothes and coats, blankets, sleeping bags, matches or other fire starting equipment, a compass and maps, flashlights, toilet paper, soap, a pocket knife and bowie knife, a fishing kit, a portable camping stove, a power inverter, backpack, paper and pencil, a signaling mirror, whistle, cable saw, bleach, insect repellent, magnifying glass, rope and nylon cord, pulleys, and a pistol and ammunition.
Many books were published in the wake of the Great Recession from 2008 and later offering survival advice for various potential disasters, ranging from an energy shortage and crash to nuclear or biological terrorism. In addition to the 1970s-era books, blogs and Internet forums are popular ways of disseminating survivalism information. Online survival websites and blogs discuss survival vehicles, survival retreats, emerging threats, and list survivalist groups.
It turns out that when you're down to your last moldy hunk of bread and giardia-laced mud puddle, letting it all melt away in a cloud of smoke for a few precious moments can mean the difference between giving up and giving the rat (eating) race another go. If history has anything to say, it's more common than you think for people to happily give up MREs and gunlord harems in return for hastening their ends with carcinogens wrapped up in tidy paper packages. In traumatic situations like war, cancer sticks are often valued more highly than food. Even in the current (more or less) pre-apocalyptic global economy, cigarettes are one of the stable forms of currency.
Every year in the US about 150 people die while out and about in national parks, more than 1,000 die in hunting-related incidents and thousands of backcountry enthusiasts get in deep trouble and require a Search and Rescue team to save them; with dozens of those folks dying while awaiting rescue. Most fatalities are the result of poor preparation. Bad weather descends and people get lost. They wander without water or shelter, often injuring themselves in the process. If they survive they often suffer frostbite, hypothermia, dehydration, trench foot or some combination of them all.