Plastic bags were patented by a company called Celloplast and by the middle of the 1960s, they were actively replacing paper and cloth alternatives in Europe. Fast forward to 1979, plastic bags already accounted for 80 percent of Europe’s bag market. At the beginning of the 1980s, two of the biggest US supermarket chains – Kroger and Safeway – switched to plastic bags. By the end of the 1980s, plastic bags replaced paper ones around the whole world.