So what your saying is that nothing bad ever happens? That your shouldn't prepare for things that you know WILL happen? I live in Southern California, we get earthquakes here and we are past due for a LARGE one. The gulf and east coast get hurricanes, should those people not worry about that? I can go on with many other REAL examples you know.
Bad things happen. However, you certainly do not KNOW that these things WILL happen. There is a fine line between say, preparing for bushfires by fire-proofing your home and building a bunker in case aliens attack. If you dedicate your life to preparing for ridiculous things that probably wont happen, then you've wasted your life. Instead of fretting about 'what if' situations, why not live the best life you can?
How many doomsayers have claimed the world will end to only have nothing happen? How many poor fools have been tricked into believing the end times are upon them only to find humanity go on as before? No-one knows when the world will end or when catastrophies will occur, so rather than spend my life in fear, I would rather live the best life I can and make the most of the time that was given to me.
Living in fear is no life at all.