I visited a grocery store to buy some food items, the moment I reached at the bill counter, the person processing the bill for me asked whether I needed a plastic bag and if I did then I would have to pay extra, when I asked him a reason for doing this, what might be the possible reason he gave me?

I visited a grocery store to buy some food items, the moment I reached

1.	I visited a grocery store to buy some food items, the moment I reached at the bill counter, the person processing the bill for me asked whether I needed a plastic bag and if I did then I would have to pay extra, when I asked him a reason for doing this, what might be the possible reason he gave me?
Answer» I visited a grocery store to buy some food items, the moment I reached at the bill counter, the person processing the bill for me asked whether I needed a plastic bag and if I did then I would have to pay extra, when I asked him a reason for doing this, what might be the possible reason he gave me?