Smoking Tobacco More Bad than Chewing Gum

It appears that the number of smokers, especially among young people, is on the rise. Smoking is banned in public places so non-smokers do not have to inhale second-hand smoke. But why not ban the sale of cigarettes altogether? The sale of chewing gum was banned in Singapore because it was not being disposed of correctly. But chewing gum is not harmful to health like tobacco. So isn't it more important to ban cigarettes?