Refusing to reduce pollution as a society and individually because everyone pollutes at least a little bit is a very lame, short-sighted, selfish excuse.  

Please learn to use the term by-product appropriately if you are going to lecture.  Plastic is not a by-product in any sense.  Plastic is a targeted product made typically from petroleum distillates.  Every molecule of plastic ever made still exists somewhere on our planet as dangerous pollution.  

We have also discovered that other renewable sources are usable for plastic production.  Will this render your entire argument against curtailing pollution moot?