With SP trying to discourage service on their passenger trains after then SP President DJ Russell hit the scene, SP would intentionally do things to show a big loss in hopes of being able to obtain authority for the ICC to discontinue these trains. Having a passenger service on the better, quicker, shorter, faster, or more populated route was not something wanted by SP at that time by any means for this reason. This continued under SP President BF Biaggini, who, in 1966, made a statement of his opinion that "Passenger Trains will be a lingering memory in approximately ten years." SP passenger trains may be a memory, but thank goodness, Passenger trains still live on today under Amtrak, 43 years later.
In a little different note on this subject, in the "This is MO-PAC handbook for Missouri Pacific System Employees", that has no date but refers to 1968 in it, that leads me to believe it was published either then or in 1969, it states on page 8, "About 89 cents out of each dollar of MoPac's income comes from general freight service, about 4 cents from mail and express service, about 2 and a half cents from switching, not quite 2 cents from passenger business and the remainder from other sources such as real estate." So in MP's eyes, passenger trains did indeed make money, but it wasn't enough "big money" to them to be worth continuing to do as many railroads viewed it at that time, compared to the freight end of the business.
This would also explain why AT&SF considered NOT joining Amtrak in 1971. In the book "Amtrak at Milepost 10" on page 54 is states that, "This pride (AT&SF's view toward their passenger trains) was talking when, at the time of Amtrak's formation, the Santa Fe considered staying out."