I'm not sure "very" applies to anything done by the royals -- they're an anachronism. And since they are supposed to be above politics, that shouldn't come into it, either. But it's probably beneficial on a diplomatic level. It depends how the Indians feel about their role as a colony.
For politics I am not sure, but for society - yes. Many fans watch at them. They give a good instance for others meeting with slum's people and donating.