Who does it belong to, then?
Who needs a pot of £9.3 billion? What's the point of it?
And why, if you found it such a burden yourself, would you want to hand it down to the next generation?
Which is what has happened. The old Duke died at a relatively young age and the new Duke- who is in his mid twenties- has been landed with the lot.
(As far as I can make out the Grosvenor fortune is the result of a singular windfall. One of them- back in the 18th century- married the woman who owned the swampy land and market gardens to the West of the City of London. Then came the Regency building boom. It's not exactly ill-gotten gains but ...)
Andrew Carnegie said, "A man who dies rich dies disgraced." That's the spirit. Mark Zuckerburg and his wife are giving away 99% of their huge fortune. Good for them.
Money is energy in token form- and a lot of money sitting in the bank is energy locked up. The proper thing to do with it is to keep it circulating. Irrigate the culture, do what good you can.