My guess is that the lit advertising sign on top of the refrigerator is for "Hot Chocolate". The lettering isn't quite readable, but the word lengths fit. The phrase below the steaming cup could be "Rich in Chocolate Flavor" or something similar.

It looks like a donut maker. They resembled a popcorn machine but they fried donuts.

I don't think the large box thing in the background is for popcorn, but I can't be sure what it is. I believe the light on top of the "icebox" is an advertising sign for coffee. I wish the picture were a bit clearer, but the image on it looks like a coffee cup. Perhaps it was some form of espresso they were serving.

Back in my ad-agency days, I sometimes drove to printers in Pennsylvania, and that state must be the last bastion of the roadside diner.

Once, I was with an account manager who was from Long Island, I believe, and we stopped in a diner for breakfast. The waitress asked us if we wanted SOS (look it up). He had never heard of it before and was somewhat dismissive when she defined it. She said, "Hold your attitude till you try some," and brought him a sample in a little white bowl.

He was astonished, declared it the best thing he'd ever had for a breakfast item, and insisted on it when we were on the road together.

Growing up in New England in the 70's I got to experience the last gasp of these places. Most of them were just called "Coffee Shop". They could be found on the first floor of many big office buildings, in bus stations, hotel lobbys etc. They were all independent but had nearly identical menus. Tuna melts, grilled and/or steamed hotdogs, open face turkey sandwiches, pre-made salads with saran wrap over the plate and a side of bright orange French dressing. Coke mixed by hand with 2 pumps of syrup followed by soda water. Really good milkshakes. Really terrible coffee that nobody realized was terrible because Starbucks was still 30+ years away. Slices of pie and cake in a glass case.

I can second the view of tomincantonga as to the wholesale destructions of SF's SOMA character. I worked just below Market Street throughout the 1980s and saw every useful small business driven out and replaced with huge banks or chain stores. Sadly missed are the delis, shoe repair shops, military surplus stores, hobby shops, etc. that used to make lunchtime errands a pleasure and something of an urban adventure.

South of Market St in San Francisco there were many hole-in-the-wall eateries. They were almost all very narrow, with a set of skinny tables & chairs along one wall, and a counter on the other. The kitchen was behind the counter, with a few at the 'back' of the eatery.
Many were shut down in the late 1970's by 'urban renewal' and the plans for the then-un-named Moscone Center. Places were put out years before the buildings were removed, and you'd see 'closing soon' signs in a lot of windows.
They were the working person's lunch menu. Chinese that way, Italian the other, and burgers and fries the third. Some pretty decent seafood places shuttered their windows and were no longer. Those in power, with the help of the banks, decided that San Francisco would no longer cater to those who worked there. It was to be a 'tourist destination', along with a pan-handler and street bum destination, but that was not known for sure at the time.
Workers, go home. We don't need you. Brown bags and 'company cafeterias' took the place of the "Jimmies' Cafe" and the 'Fish Market' and the "Hong Kong Emporium" that were so busy, so packed to the gills with people intent on easing their hunger that you stood sometimes out the door to get a seat and get back to work before time ran out. Sometimes things didn't work out that way. No longer even a memory for the SF of today. Minna, Tehama, and Natoma streets all disappeared with 'urban renewal', and I got there late. These places provided fresh, decent food at a reasonable price, and you cannot buy that anywhere in that city any more. It has changed, and I won't go back to what it is now.
tom

This lunch counter looks exactly like what it is advertised to be: a place to have a quick and inexpensive lunch. For that, it seems to be a good place. I would love to have such a place now near where I live or work. (Lunch counters unfortunately seem to be only a matter of history now.)
As for all the people complaining about the absence of hat clips: did you not notice the line of pegs for hats and coats along the wall?

Music was quite expensive compared to food.

Looks like he selected "When I Lost You" sung by Bing Crosby. Cost him a nickel, you can hear it for free here: https://www.youtube.com/watch?v=g5JporiR9oM.

The car outside is a 1941 GM product, can't tell which make. Chevrolet, probably, but other makes shared the body style. Could be a '42 if the hung up coats indicate Winter.

Will take my chances at Mackey's. Has a friendlier social vibe and this looks more like the lonely guy joint. Pass.

Anyone know what the large device is at the window? Popcorn maker? Also what is the light up ad on the icebox? (as we called it growing up).

I'll opt for the Bob Wills selection.

This is a cleaner place than the Sausalito diner, and it has ashtrays, too. No hat clips on the seats though. Can't have everything. I like waffles to boot.

I'm not eating at a place with no hat hangers on the back of the stools. I'd rather starve.

There is some wonderful focal depth in this image. Note the upholstery tacks on the chair backs: they are in focus all the way down the line. But note some of the objects off center, such as the man in the foreground: his head is out of focus, but his upper arm is sharp enough to see the weave and stitching of his jacket's fabric. The focus is selective in its depth. I don't pretend to have any hands-on experience with a large-format "bellows" camera, but I've browsed Ansel Adams' instructional notes on such matters. And this image shows the effects of tilting and swinging the lens and the film plane in concert. By contrast, a rigid lens and film plane (as with a standard camera) will only gain or lose depth, "corner to corner," according to the narrowing or widening of the aperture. Meanwhile, with a "tilt/shift" lens attached (of which I do have some hands-on experience), the tilt occurs only at the lens, while the film plane (or digital sensor) remains "squared"; the effect isn't as complex as what we see in this photo. No, I believe what we are seeing here is an example of a tilt and a swing. It isn't a casual shot. There was a lot of equipment and preparation going on at the back of this diner. An 8x10 view camera is a big rig, demanding a substantial tripod; and the tilting and swinging of the lens and film back, with the bellows extended, added to the "non-candid" nature of this composition. And yet the photographer has managed to capture a "decisive moment" of quiet psychological tension between disengagement and attentiveness.

A sandwich, a cup of coffee, and just me.

3007 16th Street, San Francisco.

It's the corner of 16th and Mission, actually. Today it's a bus stop, but the facade of the California Savings across the street (barely visible through the plate glass) hasn't changed at all apparently in 75 years.

[Excellent sandwich-sleuthing! - Dave]

Nothing like a steaming bowl of condensed "Genuine Turtle."

Thanks to Dave we see Bing Crosby has four songs on this page alone. His brother Bob only has one.

I think I'd rather eat here than at Mackey's. A lot cleaner and better maintained looking.

Click to enlarge.