Researchers have discovered that caffeine can be as physically addictive as other psychoactive substances. Some people find that they become unusually depressed, drowsy, or even irritable if they do not have their customary dose of caffeine. This is significant because as many people consume caffeine as consume any one of the other addictive psychoactive substances.
The statement 'If alcohol is a physically addictive psychoactive substance, there are not more people who consume alcohol than consume caffeine' can be logically concluded from the information above.