Having been in several evac and dig in situations, as a general rule (and there are always exceptions) most people are friendly and helpful in the first day or so in an emergency. Don’t get me wrong there are bad people out there we need to protect ourselves from or preferably avoid all together, but most people usually won't get to the point on taking what they want till they realize that they can't run down to Wally world and buy what they want, or that the gas station is closed and they pumps don't work. Unless it’s a grab the keys and run situation you can avoid most of the rush and danger involved with Evac by leaving early enough to get ahead of the crowd. You can do this by keeping a kit in your van, making a plans with your wife and family on what to do in the event of an evac, keep another kit ready to put into the van at a moments notice, keep your van’s gas tank filled (never below a ½ tank) that way you don’t have to stop and fill up when it’s time to go, and when you do get out and you think your far enough away double the distance your at when you first think that. Most people get caught with their pants down because they don’t think and plan ahead.