I am known for making some hardcore jokes, but I try not to laugh, and profit, from others people horrors. Just like I want others to not laugh from mine.
And no, I won't "lighten up and laugh, life is funny". It's like these authors never went into a painful experience. I am pretty sure their grandfathers died of cancer, or something like that. A similar slow destroying, soul crushing process. I wonder how they would feel if random people started making jokes about cancer.
But hey, we're just little monkeys, living in a sphere of indifference.