As a non-Muslim, I think even though hadith can't be traced with certainty back to Muhammad, they are still worthy of exploration.
Reason being is because in my opinion they demonstrate ways in which faithful Muslims interpreted certain verses of the Quran at the point in history at which they were recorded, or at least contain ways in which certain of the Quran verses were interpreted.
So since there is no "true" interpretation of the Quran owing to the books inherent ambiguity/use of dual words etc, we can see these as possible interpretations which historically eventuated.
It would then seem incumbent upon an omniscient omnipotent being to compose a book which foresaw these interpretations, some of which are admittedly unbeneficial to humanity, and provide greater clarification of its meaning in the text, in particular where these interpretations would come to constitute major views of Muslims living at that time (or constituting the interpretation/views of significant numbers of Muslims).
Reason being is because in my opinion they demonstrate ways in which faithful Muslims interpreted certain verses of the Quran at the point in history at which they were recorded, or at least contain ways in which certain of the Quran verses were interpreted.
So since there is no "true" interpretation of the Quran owing to the books inherent ambiguity/use of dual words etc, we can see these as possible interpretations which historically eventuated.
It would then seem incumbent upon an omniscient omnipotent being to compose a book which foresaw these interpretations, some of which are admittedly unbeneficial to humanity, and provide greater clarification of its meaning in the text, in particular where these interpretations would come to constitute major views of Muslims living at that time (or constituting the interpretation/views of significant numbers of Muslims).