People took such awful chances with chemicals and their bodies because they wanted the quality of their lives to improve. They lived in ugly places where there were only ugly things to do. They didn't own doodley-squat, so they couldn't improve their surroundings. so they did their best to make their insides beautiful instead.
Symbols can be so beautiful, sometimes.
The planet was being destroyed by manufacturing processes, and what was being manufactured was lousy, by and large.