if a student is younger than 18 years old s/he cannot buy cigarettes anywhere because the law prevents retailers from selling cigarettes or smokeless tobacco to anyone who is younger than 18. In the states of Alabama, Alaska, New Jersey, and Utah, and the counties of Nassau, Suffolk, and Onondaga in New York state, the legal age to buy cigarettes is 19.
Also, in the USA, the law for alcohol drinking is even stricter: No one under the age 21 could buy or drink alcohol on or off campus, because the legal drinking age is 21.