Tobacco is one of the GOOD drugs. The other is caffeine.
It helps productivity and concentration, improves mood, and relieves fatigue. The cost is statistically shortened life, but in vast majority of cases death happens at a relatively advanced age after the productive years are done. Also, by shorteningbold age it saves lifetime medical expenses and burden on pensions. You may consider that above as my modest proposal.
Ahhhh... I am not that sanguine on modern usage of tobacco. It was, interestingly enough, used for religious worship purposes by American Indians. Get in touch with God — smoke a cigarette? The Indians did better at that (at least with respect to what they believed was God) than we Christianized Westerners do. Outside of the lodge or wherever the peace pipe was smoked, they did not keep on puffing the stuff.