Schedule I drugs, substances, or chemicals are defined as drugs with no currently accepted medical use, a high potential for abuse, and lack of accepted safety for the use of the drug under medical supervision.
This is not true for Kratom, but it certainly is for tobacco. It has been shown numerous times in reports published in established medical journals, and acknowledged by the Surgeon General, that tobacco is highly addictive, contributes to cancer, heart disease, emphysema, and a host of other serious illnesses, and has no accepted medical uses.
https://www.opensecrets.org/lobby/indusclient.php?id=a02&year=2011