This location is listed as Fairfax Bakery in the 1950 Sanborn reference and confirmed by this 1955 Kansas City Times article to be Safeway Stores subsidiary.
Research for this location was complicated by the fact that the Styro Fabricators business located at the end of the line in 1972 moved to this location sometime before or in 1995, so it took some time to sort out all of the available information the internet had to offer. The clincher was the plot map showing that there were two Safeway locations on the Fairgrounds Branch.
At least in 1955, this location was primarily a bakery for bread products, so one could expect railcars of flours to be delivered here. The dock door is obviously from an earlier era when that product arrived bagged in boxcars; it isn't clear if adaptations were made to accommodate the unloading of airslides or other covered hoppers.
Present day pictures for reference: