In Chicago area everyone wears a mask aged 2 and over, no exceptions.
Kids wear masks in schools and preschools all day every day, with strict hand sanitising protocols. Kids do a spit test once a week. Kids age 5 and over are vaccinated, and boosters are probably going to be mandatory too.
You only see young babies out without them, in supermarkets, etc.
While entry to places like supermarkets and libraries, etc is not currently restricted, it was in the beginning of the pandemic here, with long lines waiting to get into the supermarket on a one out/one in basis. And no shopping en famille was permitted - max two people per trolley in all my local supermarkets. This restriction of occupancy may be reintroduced if omicron continues to wreak havoc.
You have to show proof of vaccination to get into any restaurants, bars, etc. The state has introduced an app so you can port your vaccine history on your phone instead of a flimsy card. A QR code is scanned at entry to venues.
The exceptions I heard about are baffling.