These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Fridge Brilliance: Dunbar and Price are around the same height, have similarly-colored hair, and wear the same kind of jacket with the fur-lined collar. So when the others throw Price out of the barracks after finding out he's The Mole, and the Germans shoot him down, it's understandable they'd think they had finally gotten Dunbar, instead of Price.
Fridge Horror: What would be done to the POWs in a prison camp where the Geneva convention is only paid lip service, when the commandant finds out that they had the mole killed and helped two prisoners escape?
It's implied that the commandant can't punish the POWs without revealing who the mole was (the Swiss representative of the Red Cross just reminded him earlier in the film against harsh tactics). He's stuck with the story that Price was an escaping POW.
In a deleted/alternate ending, all of the POWs later escaped through the hole Sefton and Dunbar cut in the gate, and later marched through the forest, all while whistling, "When Johnny Comes Marching Home Again".
During Mail Call, Marco repeatedly calls out for a prisoner by the name of McCain; during the 2008 Presidential elections, Republican candidate John McCain sure did like reminding the American people that he was a prisoner of war.
There's also Sefton proclaiming that if he escapes, he'll be sent to the Pacific and wind up in a Japanese POW camp. Four years later William Holden did exactly that.