"Why do bad things happen to good people? That only happened once, and He volunteered." - R.C. Sproul
“Why do bad things happen to good people” as a philosophical problem for Christianity assumes the presence of “good people.” There simply are none in the world today. Only Jesus Christ was a truly good person, and, as Sproul points out above, He volunteered for the duty.
Like it or not, no one is free from sin (Romans 5:12-21). Since we are not, we should suffer. As R. C. Sproul points out above and John Gerstner pointed out in “The Problem of Pleasure,” we do not deserve anything but punishment. Earthquakes, tornados, floods, tsunamis, and other natural disasters are what we deserve.
[This is a brief note on one approach to the philosophical problem of natural evil. This kind of thinking does no good to persons who are wrestling with the personal problem of evil. The personal problem of evil is what you experience when you go through it yourself. Please see this post and this post for some different approaches if you find yourself suffering.]