That's at least partly railroad culture. The BN and ATSF (BNSF) believed in running good trains, and running them well, even if they didn't pay their way. As the GN management said, "that's the window the world sees our railroad through. If the passenger trains aren't good, why would the customer ship their freight on our line?" It's been almost 50 years, and those people have retired, but the philosophy is still there. If they have to run a passenger train, run it the best they can.
UP also had good trains, and ran them well, but not being a UP fan, I can't speak to their management. The SP, of course, did everything it could to kill passenger trains, but the UP owns them now.