I don't think we have any responsibility to preserve our trash for the sake of future archaeology. The fact that humans recognise the consequences of their actions and decide to tidy up after themselves is a thing of potential historical significance. If we clear up the mess, there may still be traces of evidence left behind. An archaeologist in the future would conclude that we cared (at least some of the time).<br><br>When modern day archaeologists examine artefacts, and try to figure out how people lived and what sort of event might have caused these items to be discarded, I wouldn't expect them to be thinking that it was left deliberately for them.