Tobacco smoke is a vasoconstrictor. Alcohol is a vasodilator.
People who smoke always have the means and ability to start a fire at hand. They and their families have a better chance at survival in extreme cold weather.
Having hypothermia is somewhat similar to being drunk. Ethanol and small amounts of methanol in alcoholic drinks stimulate metabolism.
We are still not sure how habits or practices of drinking alcohol to great excess evolved. Probably procreation when extremely drunk is involved an evolutionary sense.