Why does Government Space Agencies (all) not run behind Reusable Launch Vehicles when they know slight hike in budget can significantly contribute to Cut High Costs on Launch?
Politics. This year's legislative assembly has to justify the slight hike in budget, while some future legislative assembly, if anyone, has to answer for the higher future launch costs.
If development of indigenous technologies takes time then WHY IS TRANSFER OF TECHNOLOGY not an option?
If you're wondering why, specifically, other countries don't license reusable tech from SpaceX, it's because US law restricts export of technology that could be applied to military missiles.
More generally, transfer of technology is an option; India, for example, was unsuccessful in developing their own liquid rocket engines and so licensed the Viking design from France and adapted it as Vikas.