We humans have become dependent on plastic for a range of uses, from packaging to products. Reducing our use of plastic bags is an easy place to start getting our addiction under control.
If we have any hope of finding ways for seven billion people to live well on planet with finite resources, we have to learn to use our resources efficiently. Plastic bags are neither efficient nor environmentally friendly.
Plastic bags are bad and for the most part unnecessary.
Outright bans on plastic bags may not be the best solution, but education and incentives to get people to stop using them are necessary.