It's not necessarily an oversight. Sometimes, agents and station managers just go out of their way and manage to justify giving customers much more than we are entitled to. I once had that with US when I had absolutely no status with them, was due to fly two cheapish F flights to go transcon and was arriving from a separate transatlantic DL flight which was late. The US people were fabulous and put me on a nonstop UA F transcon instead which would have costed far more. I had similarly good experiences with AF (with high status) and AZ, and indeed some years ago with BA when I was merely silver with them. Those things do happen, often when you don't even ask for them, but the point is that this is not an entitlement an one certainly shouldn't expect such mercy.