I wonder how this was received by the workers who implemented this rule. In the 2020's, this placed a burden on the service workers and often caused them physical harm by the patrons upon requesting proof of vaccination. Did the workers of the early 1900's face similar troubles?

The innovation of smallpox vaccines had been contested from the 1890's but now the argument of anti-vaccinationists rely on the modern perceptions of unproven studies. The irony in believing a falsified bit of information, claimed to have been proven my a medical study, over verified sources that also rely on medical studies that, according to anti-vaxxers, cannot be trusted.

Porter, D., & Porter, R. (1988). The politics of prevention: Anti-vaccinationism and public health in nineteenth-century England. Medical History, 32(3), 231–252.

LePan, N. (2020, March 14). Visualizing the History of Pandemics. Visual Capitalist. https://www.visualcapitalist.com/history-of-pandemics-deadliest/