After the shock of seeing Miller aim his rifle at an unsuspecting woman the audience is introduced to the possible causes of his hangups in this next scene, filmed entirely on the Columbia Ranch, the original back lot for Columbia Pictures, in Burbank (map).
Below, a layout of the Columbia Ranch as it was shows the locations of the ensuing action. The ranch is today owned by Warner Brothers and is now known as the Warner Ranch.
Then ... Miller walks past a cinema and overhears a passing girl tell her friend she has ditched her boyfriend. We get the impression he's been on the receiving end of that situation himself.
... on the back lot ... Here's where this clip was filmed (on Brownstone Street, location 1 on the map above). The cinema, with the same 'Shorts - News' sign on the marquee, is over to the right. Note the huge lights on the top of the street facade.
He walks down the street and witnesses a mother smacking her disobedient child (a public scene not uncommon in the 1950s). Clearly, it brings back unhappy memories.
Then ... He comes to a park full of canoodling couples, a sight he seems to abhor. Next to him is a fountain - at location 2 on the map above. Note the building behind him (marked by a yellow dot on the map).
... on the back lot ... below is a back lot photo of that same building, known as the Park Boulevard Apartments. The park is off to the left of the picture.
... on the back lot ... here's an overview of the park, including the fountain, taken in 1964. On a trivia note, this same fountain was featured during the opening credits each week of the Friends TV series.
Then ... Miller continues on, feeling down on his luck. This is location 3 on the map above, again on Brownstone Street but at the other end, near Skid Row.
... on the back lot ... the capture below, from a 1949 Batman and Robin TV episode filmed on the lot, shows a closer look at the buildings seen above behind Miller. (CitySleuth is indebted to an excellent Columbia Ranch website for these images).
Later we get to see just how troubled Miller really is when, in a moment of self-inflicted punishment, he holds his hand against an electric range burner. His subsequent visit to a doctor will turn out to be pivotal to the denouement of the story.