It's 2023. It's funny people still wear masks.
Many of those wearing masks recently had COVID, and while no longer testing positive, are still within the 10-day window of the CDC guidance.
Some are people with high risk factors or simply people who are COVID-averse.
The others are lizard people who are trying to hide their true identities. If you spot any of these, you should rip their mask off and run away cackling about how you've exposed their infiltration of the planet, and how they'll never succeed.