Looks more like they are unloading the car. The car is sitting next to lumber sheds, and the load appears to be bags which are to big to be cement or plaster. Nor does the bag sag in the middle, indicating it is lot heavy. It could be bags of vermiculite, used in insulation, which would be shipped in a NP boxcar as the main mine was in Montana. A lumber yard in Florida would be receiving bags of vermiculite, not shipping it out. The forklift does not have pallet, but rather it appears the employees simply laid some planks on the forks to make a platform for holding the sacks. Once the fork is loaded, they will drive it to the storage building and unload the sacks into the building, out of any weather. All done by hand.