Given current events, a recession caused by the top 1% that has financially gutted the lower 75% and caused many people to lose jobs, benefits, insurance the people most vulnerable in any disaster are also the least financially and emotionally capable of assembling any reserve supplies. These are people struggling to keep a roof over their head, feed the kids and keep enough gas in the car to get to work. Which assumes they have a job.

The FEMA list is much more practical. Its emphasis is on keeping things simple, as inexpensive as possible, and getting the most bang for any effort put into it. It does a pretty good job of it. You can quibble over individual items and amounts included, I'm not enthusiastic about some of the trade-offs and compromises, but they cover the bases and give you something to work with to cover most needs.

If every household had such a kit you would smooth a lot of the rough edges on any disaster. It also has to be pointed out that a three day kit may, if you are careful and husband resources, get you through six days. The main limitation is water supply. Water, which can be problematic after a disaster, is fortunately the easiest resource to pick up before a disaster. A rinsed bleach bottle full of tap water is easily arrange and is close to being free. A six-pack of bottles water is inexpensive.

After an event water from toilet tanks, water heaters are resources. Water repositioned by filling garbage bags and laid flat in the tub are handy. All of those are cheap and available with minimal investments in cash and effort.