sorry, you meant to say a net negative effect. A benefit is a positive so that's a confusing sentence.
The idiots who get recognition or promotions for being "innovative" are the winners.
Sorry JC but you really seem bitter sometimes. Clearly it's a positive for the ocean as bags that are issued by supermarkets often are discarded in the street and end up in waterways and then in the ocean. Then they cause problems for marine life that ingests them as food which often means they die.
So it's a net benefit to the environment however you slice and dice it. Single use plastic bags are a waste of energy and resources.