Just to clarify its not just plastic bags. My concern regarding that is actually the legal mechanism used to ban plastic bags among other nanny state legislation.
The point of that is when they can force businesses from supplying plastic bags , a perfectly legal item, they can also take things much further and ramp it up to banning or restricting far more serious things, hence the eventual complete control of any means of production no matter what.
Down the road, it contributes greatly in destroying the freedom of having a free independent market.