If you made a draft email with those details, then GMail sent that draft without your authority then they too would be in breach, albeit unwittingly. That seems

If you made a draft email with those details, then GMail sent that draft without your authority then they too would be in breach, albeit unwittingly. That seems like a reasonable analogy to what happened in the OP, assuming it was a bug and not some 'growth hacking' plan as others have speculated.