Monomers like ethylene are a by-product of splitting oil; you still need polymerization and processing of the polymers (e.g. extruding, moulding, etc).
It's non-sequitur to say that the process is not wasteful because part of the initial work is done to obtain gasoline. Oil itself is a limited resource.
It's non-sequitur to say that the process is not wasteful because part of the initial work is done to obtain gasoline. Oil itself is a limited resource.