That's assuming those places don't have HVAC systems, which many more modern buildings have. We can theorize about this all we want, but poking around a bit there seems to be very little data on the topic, and what exists doesn't point towards AC being a significant vector for the virus spreading. It can spread it, but I'm not seeing anything indicating it's a serious problem or behind the current surge we're seeing. At least not more than other factors like low vaccination rates and unvaccinated people returning to normal once more.