when I was a kid we used motor oil as a weed killer along fences...bad? Not sure.
Oil comes from the earth...
Cars and such leak oil.
Roads are made of oil (tarmac/blacktop/tar and chip)
Nobody talks about all the rubber out there ... tires wear out and the rubber goes where?
Like global warming - EVERY city is warmer than ANY country setting..and cities keep growing. Buildings/paving hold heat more than a pasture or forest. You burn gas/diesel or heat your house (or run your a/c) and you make heat - and LOTS of it. Run something in an enclosed area and the area heats up..why would the planet not work teh same?
Yet there's no movement to reduce pavement, heat absorbtion, etc.
As for GMO's and the like, go read "no blade of grass', a novel from the 70s or so, about a gov't 'agent orange' type weapon that gets loose. It kills all grass-based life - grass, but also corn, wheat, rice, etc.
the more we go to a monoculture the more vulnerable we are.