Final answer:
Licensed establishments may impose a minimum purchase requirement, but such policies must comply with state and local regulations. The National Minimum Drinking Age Act of 1984 does not mandate minimum drink purchases; it addresses underage drinking by setting the legal drinking age at twenty-one. Enforcement and legality of establishment policies regarding drink purchases are subject to local laws.
Step-by-step explanation:
The statement that a licensed establishment can require customers to purchase a minimum number of drinks in order to gain entry to, or remain on the premises is somewhat complex and depends on local laws and regulations. Fundamentally, there is no direct provision in the National Minimum Drinking Age Act of 1984 that requires customers to purchase a minimum number of drinks. This federal law was designed to address public health concerns related to underage drinking by requiring states to set the minimum legal drinking age to twenty-one, under penalty of losing federal highway funds. However, businesses such as nightclubs and bars may set cover charges or minimum purchase requirements for various reasons, including economic demands influenced by concepts such as threshold population, which was described by Christaller in the context of merchants and service providers needing a certain number of customers to stay in business.
Still, while businesses may impose such requirements, they must also adhere to state and local regulations which may have provisions against certain types of coercion or limitations on consuming alcohol. For instance, some local laws may prohibit practices that encourage excessive drinking, such as "all you can drink" deals. Similarly, a licensed establishment must comply with all laws related to the safe service of alcohol, including not serving to minors or visibly intoxicated persons. Therefore, while establishments may have entry policies related to purchases, the legality and enforcement of these policies can be nuanced.