Tobacco is surely a moral evil. It is slow suicide, and it kills the people you love (cancer in spouses from second-hand smoke is very common), and if it doesn’t kill them it harms their health in other ways (making them sick more often, asthma, etc.)
Smokers are always chatting with other smokers, since they’re in the same areas right outside smoke-free buildings. You don’t think this doesn’t lead to inappropriate interaction with the opposite sex? Of course it does.
We don’t give potheads a free pass. Marijuana is assur too. People don’t think they deserve jail anymore, but that doesn’t mean we approve.