The stories of alcoholic beverages historically being safer to drink than unfermented ones are apocryphal at best; however, as any 17th-century sailor would tell you, the addition of some spirits to potable water that's been sitting around for too long will make it much more palatable. Liquor distillation was originally invented in part for medical purposes, and alcohol can be used as a solvent to dissolve medicinal herbs -- and also to knock out patients during good old-fashioned fallout-shelter surgery. High-proof alcohol can be used as an antiseptic, and it does a great job of cleaning wounds and preventing infection.
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?
Modern-day survivalists aren't generally regarded as the most sane people on the planet. A quick look at any one of the disturbingly common and frighteningly thorough shopping lists they post online drives home the fact that anyone who self-identifies as a "prepper" most likely went off the deep end a long time ago. Sure, it's fine to keep a few extra cans of food and cases of water around for an emergency, but if you start adding body armor and butt paste to your stash, you might want to tell George Miller that it's time to see other people.
These individuals study End Times prophecy and believe that one of various scenarios might occur in their lifetime. While some Christians (and even people of other religions) believe that the Rapture will follow a period of Tribulation, others believe that the Rapture is imminent and will precede the Tribulation ("Pre-Trib Rapture"). There is a wide range of beliefs and attitudes in this group. They run the gamut from pacifist to armed camp, and from having no food stockpiles (leaving their sustenance up to God's providence) to storing decades' worth of food.
When you go back to the last depressing days when we were in a survival mode, the last one the Y2K of course, before the 1970s, what had happened was you only saw this one element of survivalist, you know, the caricature, the guy with the AK-47 heading to the hills with enough ammunition and pork and beans to ride out the storm. This is a very different one from that: you're seeing average people taking smart moves and moving in intelligent directions to prepare for the worst. (...) So survivalism in every way possible. Growing your own, self-sustaining, doing as much as you can to make it as best as you can on your own and it can happen in urban area, sub-urban area or the ex-urbans. And it also means becoming more and more tightly committed to your neighbors, your neighborhood, working together and understanding that we're all in this together and that when we help each other out that's going to be the best way forward.
The article mentions “The Commander Prepper”. I get it, yet I don’t get it! Especially, when bounced against “commanding and leading”. I guess if taken in the context of just prepping, I sort of get it. But if associated with after the catastrophe trigger has been pulled, I definitely have a problem with it. I do not know the leadership experience the author has had or even claims to know, but I do know from personal experience that situational and operational awareness, eminent actions and the make-up of your individual team dictate the three leadership styles. There is not enough time for discussion here, but you should research this on your own. Their is no replacement for hands-on experience, but leadership disciplines can be quickly studied, learned and put into practical use.

Astronauts are provided with survival kits due to the difficulty of predicting where a spacecraft will land on its return to earth, especially in the case of an equipment failure. In early US space flights, the kit was optimised for survival at sea; the one provided for John Glenn on the first American space flight in Friendship 7 contained "a life raft, pocket knife, signaling mirror, shark repellent, seawater desalting tablets, sunscreen, soap, first aid kit, and other items".[5] A survival kit was provided for the Apollo program which was "...designed to provide a 48-hour postlanding (water or land) survival capability for three crewmen between 40 degrees North and South latitudes".[6] It contained "a survival radio, a survival light assembly, desalter kits, a machete, sunglasses, water cans, sun lotion, a blanket, a pocket knife, netting and foam pads".[7]
Earthquakes, tornadoes, and hurricanes can cause you to leave your home or even be trapped there. Roads could be blocked due to fallen trees, power lines, or even damaged earth from the natural disaster. Rescue crews can not be in all places at once. You may have to wait it out for quite a while before its over. You won't be able to go to the store or to the corner market.