If we stop using plastic bags and use paper bags instead, isn't that going to cut even more trees?
This is a deeper question than it may appear on the surface.
You could send the paper manufacture off to a third world country and have them decimate their forests and fill their waterways with dioxins and other organochlorines. Then move on to the next candidate for development.
Or you could establish a renewable forest industry on land that may be marginal for existing farming. Then local paper mills using chlorine-free bleaching. The benefits are jobs, an enlarged tax base, an export industry and carbon credits if they still exist.
I doubt the second option would happen without an interventionist government. You see where this is leading...
Paper is not 100% free of environmental cost, but at least you can put the waste in your fireplace or send it off to be turned into packaging.
OT, wood is an underrated resource. Here in NZ we were no better than anyone else in decimating our native forests. But the renewable plantings are being used for things like laminated structural beams in earthquake zones to replace steel in multi-storey buildings, and the waste turned in to pellets for heating. Then end result is better quality stuff and multiple income streams for the suppliers and manufacturers. Again, the tax base gets enlarged.