ShanghaiBill,
Your home or the high-rise in which you work are unlikely to be consumed by fire. Are fire drills important?
Is it important to know where, for example, the nearest exit is on an airplane or in a theater, even though it is extremely unlikely that you will be confronted with a disabled airplane or a theater massacre-in-the-making?
Preparation for disasters - whether in terms of visualizing the scenario or actual drills to practice response - can be extremely effective in boosting survival.
If you are interested in some of the academic study on this and related topics, see this book,
The Unthinkable - Who Survives When Disaster Strikes, and Why. The author did a tremendous amount of research, distilling academic papers and studies of recent and not-so-recent disasters to explore human behavior both culturally w/r/t preparedness and engineering, and in the context of the disaster events.