I doubt there's a single soul outside the film industry who gives the slightest damn about whether the actors are at the first showing of a film in their country/continent/whatever.
The world has changed. Film studios (or candle markers) do no have a right to continue to make money the same way. They can adapt or die.
Interesting comparison. My favourite is "weavers":
Why not just have ONE worldwide premiere, and journalists from various countries can cover that single meaningful event?
Japan is a huge market for international film releases, so some of the actors do show up once in a while, but not often and certainly not for most movies.
There are popular television shows that cover all the current Hollywood releases of the week, including those without any scheduled local release date. Lack of media attention is not the problem.
Inertia, fear of change, and localism (who cares about the rest of the world?) is the problem, but it is slowly but surely getting better.