&gt; If the costs of cleaning up people throwing plastic away are being met by a tax, why would one care whether plastic continues to be used for new items and people continue to throw it away?<p>Because it&#x27;s possible that the costs are not entirely monetary. I agree that there is more nuance to this debate, though. In my opinion one-time use objects made of plastic are appropriate in some contexts (medical care, for instance) and less appropriate in others (plastic silverware).