Cigarette smokers are not a bad influence compared to cocaine addicts. The influence of addiction is relative to the degree it hampers one's journey within reality. Influence here applies to how the action affects others but it also applies to how it affects yourself - for if your journey is affected, that changes how you in turn might affect the journey of another soul. Unfortunately, society often sticks its nose into the business of the journeys of individual souls. It places inappropriate restrictions upon those journeys in a good-intentioned manner that often has the reverse affect.
Drug use is one such case.
By outlawing drugs, society compounds the problems of the addict in terms of his repercussions in the afterlife. Outlawing drugs isn't done in the context of doing what's best for a particular soul's journey, but rather with the self righteous determination to impose one's own morals upon others in a power play of grand showmanship. Keep in mind that in many of these cases, we are not protecting society from the individual but rather attempting to protect the individual from himself. We are trying to protect him from his own journey for which he himself will be held accountable through the ripple effect. We are placing more pressures on families, friends, neighbors, and even races.