One way that intelligent people prepare for future disasters is they look to past disasters to gain insight into what might happen.
From those reference points, preparedness-minded people can triangulate how events might unfold and make adjustments, if necessary, to ease the pinch.
One treasure-trove of information comes from a blog post that Bayou Renaissance Man wrote back in 2008 regarding the ripples from Hurricanes Katrina and Rita. I am going to lean very heavily on Fair Use and display just a few tidbits that spoke most loudly to me.
I chose to quote two of the bullet in their totality because they the spoke most loudly to me.
Let me reiterate: This is not my work. I am "borrowing it" from Bayou Renaissance Man. I cannot even claim to have found it; a kind gentleman pointed it out to me. If it speaks loudly to you, it is probably worth your time to follow the link shown above and read the his entire post.
The original post is a multipart, mega-post. I will identify the sub-post and bullet that I am quoting:
1:3 Plan on needing a LOT more supplies than you think. I found myself with over 30 people on hand, many of whom were not well supplied: and the stores were swamped with literally thousands of refugees, buying up everything in sight....
1:4 In a real emergency, forget about last-minute purchases.
1:11 Have enough
moneycash with you for at least two weeks.
1:13 Don't rely on government-run shelters if at all possible. Your weapons WILL be confiscated
1:14 Warn your friends not to bring others with them!!! I had told two friends to bring themselves and their families to my home. They, unknown to me, told half-a-dozen other families to come too - "He's a good guy, I'm sure he won't mind!" Well, I did mind . . . but since the circumstances weren't personally dangerous, I allowed them all to hang around. However, if things had been worse, I would have been very nasty indeed to their friends (and even nastier to them, for inviting others without clearing it with me first!). If you offer a place of refuge for your friends, make sure they know that this applies to them ONLY, not their other friends. Similarly, if you have someone willing to offer you refuge, don't presume on his/her hospitality by arriving with others unforewarned.
2:1 Route selection is very, very important.
3:1 People who were prepared were frequently mobbed/threatened by those who weren't. ...neighbors who had not prepared all came running after the disaster, wanting food, water and shelter from them. When the prepared families refused, on the grounds that they had very little, and that only enough for themselves, there were many incidents of aggression, attempted assault, and theft of their supplies...in some cases, shots were fired.
3:2 When help gets there, you may get it whether you like it or not...In one incident, a family who had prepared and survived quite well were ordered, not invited, to get onto a truck, with only the clothes on their backs. When they objected, they were threatened. They had pets, and wanted to know what would happen to them. They report that a uniformed man (agency unknown) began pointing his rifle...
Another aspect of this is that self-sufficient, responsible families were often regarded almost with suspicion by rescuers. The latter seemed to believe that if you'd come through the disaster better than your neighbors, it could only have been because you stole what you needed
3.3 There seems to be a cumulative psychological effect upon survivors. This is clear even - or perhaps particularly - in those who were prepared for a disaster. During and immediately after the event these folks were at their best, dealing with damage, setting up alternative accommodation, light, food sources, etc. However, after a few days in the heat and debris (perhaps worst of all being the smell of dead bodies nearby), many found their ability to remain positive and "upbeat" being strained to the limit. There are numerous reports of individuals becoming depressed, morose and withdrawn. This seemed to happen to even the strongest personalities. The arrival of rescuers provided a temporary boost, but once evacuated, a sort of "after-action shell-shock" seems to be commonly experienced. I don't know enough about this to comment further, but I suspect that staying in place has a lot to do with it - there is no challenge to keep moving, find one's survival needs, and care for the group, and one is surrounded by vivid reminders of the devastation. By staying among the ruins of one's former life, one may be exposing oneself to a greater risk of psychological deterioration.
4.3 Your personal and/or corporate supplies and facilities may be commandeered without warning, receipt or compensation.
4.5 Those who thought themselves safe from the disaster were often not safe from refugees. There have been many reports of smaller towns, farms, etc. on the fringe of the disaster area being overrun with those seeking assistance.