If consumers doesnt consume rationally the better product wont neccesarly replace the worse product. In most cases this doesnt matter, but when it comes to environmentaly damaging products it does.
There are many cases when what you consume effects me. If you buy a refigerator with freon, a car with poor particulate filter or even the incandescent bulb that just so slightely increase air pollution by slightely higher energy consumption. Although I agree that banning the incandescent bulb doesnt really make a significant difference.
But in those cases the free market seems inefficient, would the emission standars for cars be what they are today without regulation? Would freon be gone from refrigerators without a ban? Since consumers in many cases doesnt consume rationally I dont se anything wrong with some bans or regulations as long as they dont infringe on anyones living standard.
I seriously doubt most people spend any time rationalising over what toothpaste or light bulb they should buy, I hardly know anyone that does and that includes most I know that are very well educated and intelligent.
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Familiarity usually seems like the most important thing.