I guess it is human nature – when you have so much money that it can help many future generations of your progeny, you do your best to make sure it gets to them.

Smarter still is to use some of that money to ensure that they survive at all.

The client, a senior partner at Goldman Sachs, wanted him to design a family house in upstate New York with a difference. It wouldn’t just be completely ‘off the grid’, with its own power and water supplies, but — and there isn’t yet an architectural term for this — it would be post-apocalypse. The conventional house would be mirrored below ground with pretty much identical living quarters that would be completely secure and so self-contained that there would be facilities to hydroponically grow plants and vegetables without soil.
[Source: The Spectator]

This isn’t a unique case, another prominent example is the Walton (Walmart) family and their compound. What pleases me is that (seemingly) such preparations are occurring in a post-2012 era.

The article mentions a 2nd Wall Street millionaire:

The strange thing was that when my friend rang a mechanical engineer for advice on a few technical details, rather than be gobsmacked, the engineer said he’d been working on pretty much the same brief for another Wall Street titan. Only he wanted a moat, too. ‘What do they know that we don’t?’ the architect asked me.

I would do the same, if I had the cash. But presumably I’d invest in weapons and secrecy over a moat.