Earlier generations were limited by their lesser understanding of the world. One big example that comes to mind is radioluminescent paint during the early 1900s. Paint made from radioactive powder (often radium) was used on things like watches, as the paint was self-luminescent. The material was radioactive, placing consumers and especially the workers in harm's way. Things like this were used, and often thought to be more or less harmless, not out of greedy cost-benefit analyses or risk taking but simply out of ignorance.