So, since you mentioned the National Anthem and standing etc. I was attending ROTC summer camp the first time I saw "Patton" in the base theater. The opening has the General walking in and someone calling the room to attention. The whole audience, admittedly a lot of kadets, popped to attention and stood there until George C. Scott said as you were. Back in those days, the movies at the base always opened with NA and of course everyone stood.
yep on the AAFES theaters...
Also, into the early '90's, I will admit to watching TV late at night in our apartment in Gainesville after having consumed alcohol and standing at attention when a broadcast channel would go off the air.
Quietest packed AAFES theater I was ever in: earlyish 1987 at Grafenwhor Training Area in Germany, at the theater in the training area (not main post nice theater which was off limits to us people actually training at Graf) watching Platoon with about 700 other dudes in dirty uniforms.
Loudest packed AAFES theater I was ever in: summer 1985, Disney Theater at Ft Knox. OSUT was 16 weeks long, and we were treated nearly the same on the last day as on the first day. 16th Cav (unlike 15th Cav) got ZERO privileges during the 16 weeks... in the mess hall, no soda drinks and no short order food (no hamburgers type stuff), no going to the PX other than as a platoon to get toiletries and stationary under the watchful eye of DSs. But on the night after our Phase II testing, DS Lamboy said in his heavy PR voice, "Fuk it, we're going to the movies" and we watched Rambo II that night. The next morning sucked.