We have thought about this as well. If there is an emergency that affects a metro area, you need to be able to get out of the area and then refill. In an ICE, it's easy to drive 200 miles and then tank up in 5 mins. In an EV, you might be able to get 200 miles, but it's much less likely that you'll be able to refill in under an hour. If many people are evacuating, charging stations will be overloaded. Trickle charging can be done almost anywhere, but that can take a really long time.