Brands tend to replace hands as a matter of policy, if they need it or not. This is particularly common on chronographs, because each time you remove and reinstall the hands, the tubes get stretched slightly. This means that they are not as tight on the posts, and actually press down further on the posts before they get tight. This risks hands being too close to the dial, or hands that don't stay put under the forces generated during a reset. A service center is never going to take the time to repair this or even be bothered to install them to check the fit), so they simply walk to a drawer and pull out a new set.
On the dial, I don't think they always replace them due to the lack of glow - that may depend on the service center in question, but surely if the lume looks iffy and might flake off, they will.
