Cows eating the bags sometimes die. These plastic bags and plastic cups do not decay. Their terrible contaminating influence will be with us for much longer then we and many generations after us will live. Most of the plastic ends up in the holy Yamuna causing danger there. Later the plastic goes into the ocean which is already a plastic infested body of water.
Plastic is never clean or pucca.
It is unacceptable to our Vaisnava culture for eating. Plastic is made from Fossil remnants with a hazardous chemical process. This turns the dead body fossil remnants into plastic, fuels and a host of other synthetic materials. Mahatma Gandhi would have made a revolution against all these plastic cups and plastic materials which steals the income from the simple farmers and khadi producers for some multinational company. Clay cups and leaf plates are perfect and give a high standards where Bell metal or Gold is not available.