The color, the pump design, and the perforated detailing are all very indicative of what was popular at the time.
You'll notice that the heels are a bit thinner and higher than what was available in the 1920s, but they still weren't super-thin or tall, like stilettos and other high heels that would come later in the century.
Because of The Great Depression, fashions around the world were a bit more conservative than they had been during the flashy flapper era of the 1920s. And, while ready-to-wear fashions had become more popular than ever during the 1920s, the tough economic climate of the 1930s meant that, once again, some women would return to sewing their own clothing. The lines of the clothing were very simple -- almost plain. Hence, shoes of the era weren't particularly fancy either.
There was a lot of variety, however. Classic pumps, like the ones shown here, as well as oxfords, Mary Janes, and even sandals, were extremely popular during this period. But, instead of being made from fine fabrics, and detailed with expensive or intricate embellishments, shoes of the 1930s often got their details from perforations, straps, contrast stitching, or from being two-toned or multi-colored.