It also ignores that animals produce the manure that is used to fertilize soil to grow crops in.
We use manure because it's coming out of the gills of the animal ag industry, not because it's necessary to enrich crop soil.
Just because plastic bags are ubiquitous doesn't mean it's the only nor best way to carry items around, nor that we'd lose the ability to transport goods if they were phased out, nor that they don't come at a cost despite perceiving them as free.
> We use manure because it's coming out of the gills of the animal ag industry, not because it's necessary to enrich crop soil
Crop soil needs fertilizer somehow
What is your alternative to manure?
Bonus points if it uses less energy to produce than animals, produces less CO2 than animals, takes up less space than animals, or also produces food at the same time
Done any farming lately? You would not get enough yield to feed people without fertilizer. Of course it can be produced from a source different from manure. Nitrogen-based fertilizer is produced from cheap natural gas... oh wait... that is gone,too.