My grandfather's brother, John Ivor Davis/Davies (on the left in the above picture), worked as a delivery man/driver for Strawbridge & Clothier Department Store in Phildelphia in the early 1900's. Wikipedia has a page on the store's history that included the following:
The store began as a dry goods store and was founded by Quakers Justus Clayton Strawbridge (1838-1911) and Isaac Hallowell Clothier (1838-1911) in Philadelphia in 1862. In 1868 Strawbridge & Clothier purchased a 3-story brick building on the northeast corner of Market and 8th Streets in Center City Philadelphia, which had been Thomas Jefferson's office in 1790 while he served as Secretary of State, and opened their first store. But soon the old building was replaced by a new 5-story department store offering a variety of fixed price merchandise under one roof.
In the above picture (dated 30 Oct 1912) he's driving the delivery truck. The picture below was taken at a "farwell party" on 18 Apr 1915. John Ivor is in the back holding the child (not his child).
You can see a photograph of the store with delivery trucks and drivers lined up here. Based on the style of vehicles, it appears the photo was taken about the time John worked for the store.
In 1911, the Strawbridge motto evolved from "Small profits, one price, for cash only," into the trademark "Seal of Confidence," which featured William Penn and the chief of the Leni-Lenape shaking hands to cement a treaty. You can see their trademark on the postcard pictured at Remembering Great American Department Stores.