Final answer:
The lawfulness of displaying alcohol at an athletic contest depends on regional laws and can vary by location. The temperance movement and Prohibition era laws have historically influenced regulations on the public consumption of alcohol, including at sporting events.
Step-by-step explanation:
The question of whether it is lawful to display publicly fortified wine, spirituous liquor, or mixed beverages at an athletic contest is dependent on particular laws and regulations which can vary by region and context. However, in general, the movement against the public consumption of alcohol, known as the temperance movement, and subsequent legal restrictions, including those outlined in the 18th Amendment, suggest that there are legal limitations on such displays and consumption. It is worth noting that the temperance movement did indeed stem from concerns over new social conditions, such as increasing urbanization and immigration, leading to the Prohibition era laws that regulated the manufacture, sale, and transportation of alcoholic beverages in the United States.
Given the cultural and legal histories regarding alcohol consumption in the U.S., it is typically necessary to follow specific licensing laws and local regulations when it comes to alcohol at public events. The correct response to the original question, though, requires additional context about current laws and location-specific ordinances which may govern the display and consumption of alcohol at public venues, including athletic events.