Dark humor is not cruelty wearing wit's clothes; it is the survival mechanism of people in the middle of situations that would otherwise be unbearable. Those who find it offensive have perhaps not been close enough to the extreme yet; those who find it sacred have, and they know what it cost. Nasreddin made jokes about poverty, death, and injustice not because he was indifferent to them, but because the joke was sometimes the only dignified response available.
Each step builds on the last.