About drain pipes being made of plastic, or PVC: PVC is a type of plastic.
About PVC pipes being made of combined plastic and vinyl: This statement is incorrect because PVC pipe is made from polyvinyl chloride and is not a combined plastic.
Polyethylene drainage pipe is chosen for different applications than PVC pipe. Some people choose this material because it is the most cost efficient product for the job.
It is true that ceramic pipe does not contain any fossil fuel whereas plastics are typically derived from natural gas, the amount of fossil fuel required to dig and transport the clay, manufacture and fire the ceramic pipe and transport the much heavier, per linear foot, ceramic pipe to the job site makes the fossil fuel savings of using ceramic pipe non-existent.