You joked about recycling old cars. While I have no doubt restoring an
old car is more environmentally damaging than say GM turning out one
Chevy, I wonder if there is all that much difference. While the old car
has to be degreased and any new parts have to be made somewhere, I'm
sure there is considerably more electricity used (which might easily be
coming from a coal fired generator) throughout the manufacturing process
and think of the number of workers driving to GM's plant, etc, etc.
Unless you're doing the sort of restoration that starts with a serial
number plate or a frame rail, and nothing else, I doubt you could
rival the amount of resources that are consumed and the pollution
generated by the manufacture of a new car.