I was curious about when and where these core charges started. It looks like it was the result of WW2 and the shortage of steel and other materials forcing both the military and civilian manufacturers to turn to recycling and rebuilding parts out of necessity. After the war, the remanufacturing industry was large enough to stand on its own and the concepts stuck around. Some hazardous items like lead acid batteries have legislation helping to enforce the core charges but the rest seem to be market driven.