Some customers will buy goods from the store using plastic and will intentionally or unintentionally throw the plastic of the purchased goods on the ground, roadside and so on. 

Plastics is also a waste that cannot be disposed of. That is why we need to reduce the use of plastics. The more people who contribute to this plastics disposal, it is increasingly likely for this world to be severely polluted.

So, if we stop using plastics and start using paper bags while shopping, we can reduce pollution on this earth.