Various forms of plastic bans keep getting imposed year after year in different places in India.

Nothing practically happens because:

a. Police has better things to do than round up people and shops carrying plastic bags. They may probably take a bribe from the shop to turn a blind eye.

b. There's no really low cost and convenient alternative in many cases - in spite of a lot of shops in India using recycled newspapers for packaging.

Home delivery which is widespread among the richer classes is at least partially helpful since shops bring things in their own bags. However most of India is not rich