I think he fact that things have become a lot safer also plays a role. If you live in a society where many kids die before they are ten years old, mothers dying at child birth is 'normal', survivors of diseases such as polio and smallpox are common in the streets, and quite a few factory workers get seriously injured in the work place somewhere in their career, a disaster maiming, say, 10 people, barely sticks out from the background noise, so isn't really worth worrying about (in even more extreme circumstances just a century ago, some soldiers who lost a foot or leg in the trenches in World War One were happy because it meant they would be sent home)
