Maybe not all that unusal as I believe about this time frame the passenger crews were still handling LCL freight until the unions "won" in a ruling by the Railroad Labor Board so that they would get freight pay in addition to passenger pay for handling LCL traffic...
See also a RB Jackson photo dated 7/12/1939 on page 172 of CRRM Annual No. 24 captioned thusly:
"This 11 car train is one of the longest narrow gauge passenger trains ever photographed in scheduled service. It includes two mail & baggage cars, six baggage cars, two coaches and a parlor car. The combination of trains 115, the San Juan (westbound)and 425, the Santa Fe mixed, is (shown) heading south from Alamosa to Antonito on July 12, 1939. (Richard B. Jackson photo California State RR Museum 21766
"