A lot of places in Vegas will card everybody regardless of age. But never been knocked back with my NSW DL (but also done it all over the East coast, especially NY & Boston - never got asked for a passport, NSW DL was fine).
Thinking that there's 50 states in the US, I reckon some of these bouncers wouldn't be able to name all 50 states and not recognise our DL as foreign - just another state to them.
Passport for government/military tours is definitely a thing - I was lucky enough to tour inside the pentagon (had a friend who worked in the embassy). A lot of aviation museums located adjacent/on USAF bases will require a passport to go into certain areas (from memory needed it to go on the tour at Davis-Monthan AFB - aka the boneyard). I think even some of the bus tours at Kennedy Space Centre need to see your passport when they go into Cape Canaveral (was USAF, now Space Force)