Las Vegas threw open its doors to visitors again on June 4, and those who came streaming into the city’s hotels and casinos were greeted with a whole new set of health protocols. Temperature checks, hand-sanitizing stations, plexiglass between players at gaming tables and six-foot social-distancing markings throughout properties reminded everyone of the evolving “new normal.”

Face masks were a big part of the plan; they were worn by all employees and offered to all guests. At Caesars Palace, even the statues were wearing them.

Those guests, however, apparently did not get the message. No more than 20% of them, and probably a lot fewer, wore face coverings, according to David G. Schwartz, gaming historian, professor and associate vice provost at the University of Nevada, Las Vegas, who visited Bellagio and Caesars Palace during those first reopening days.