From a global warming perspective, plastic bags are generally better for the environment because they are extremely light, therefore use less gas to ship. However, plastic bags often end up in nature, where plastic particles end up in animals and plants.
Unfortunately, most people are so completely brainwashed that they feel proud of themselves for putting their plastic in the (open topped) recycling bin where it blows out, goes down the drain and ends up in the sea. They imagine that putting it in normal (closed top) rubbish will cause it to end up in a seagull's stomach, starving it to death while "recycling" allows them to sit back and gloat about how lucky they are to have the opportunity to save the planet.
