It's incredibly bad when plastics and disposable batteries start getting burnt, as is inevitable when burning is the primary trash disposal strategy.
Of course, in some areas of the world, both uncontrolled trash burning and unregulated trash dumps are used.
I think the other post may be talking about people who burn their trash at home, instead of at an industrial scale? It seems like a neighborhood of people burning their batteries and plastics would not be great, compared to an industrial incinerator.
Or maybe I'm way off base.
Burning trash is bad. Incinerating properly is crucial.
My uncle used to pick up all the food scraps from a local restaurant and feed those to his pigs. It made a mess in his pickup truck, but it was a lot cheaper than commercial pig food.
Trash bags are just a great time saver and more sanitary. I sure like them.
Its a little more labor intensive, you can't dump liquids in a paper bag at least without paper towels, etc.