Friends of mine who have had a passing familiarity with this world over the years have told me stuff like, “money is the way they keep score.” Well, usually you “keep score” in games that have a beginning and a middle and an end, but this goddamn game they’re playing doesn’t have an end. It just keeps going and going and going, and they keep accumulating more and more millions and billions, and they keep buying shit with it — Gin Lane estates, $1.5 million Ferraris, Gulfstream 550s, 220-foot-long mega-yachts.

I have a friend who takes care of a boat for a billionaire who owns a very well-known sports team. Every year, that boat — it’s about 32 feet and it cost a couple million — is put on a trailer down in Palm Beach and it’s driven up here for the summer. Last couple of years, the billionaire sports team owner hasn’t taken the boat out on the water for even one hour. It’s so underused that my friend has to “exercise” the boat every couple of weeks to keep the engines in good shape, so we take it out and zoom around — it will do 35 knots; it’s a hell of a lot of fun — and then we tie it up in an expensive marina. When September rolls around, the boat is put on a trailer and hauled back down to Palm Beach, where it goes back in the water and then . . . who knows? It probably just sits there.

Which brings us to the question raised in the title. I have to say, I don’t have a clue what’s up with rich people. I mean, I’ve got friends here in Sag Harbor who do stuff like building teak decks and painting houses and plumbing and electrical work, and every single one of them has trouble getting paid when it comes to summer people, which is to say, when it comes to rich people. Working for locals isn’t a problem.

But rich people? They don’t pay on time and they fight over the bill. I don’t remember asking for that concrete, they’ll say, pointing to the bill. Well, sir, you can’t put posts in the ground for your deck if you don’t sink them in concrete, so that’s why the eight sacks of concrete are on the bill. Or they’ll complain about paying two or three grand for pipe and have to be reminded that’s the stuff the water goes through, and building codes say it has to be copper, and copper costs money. The thing is, none of them — not a single one of them — will just take the damn bill and pay it. They have to nitpick things to death before they write a check on an account that’s linked to some offshore trust in the Caymans.

It's not really because investors think the proposed tax overhaul would unleash enormous growth by creating new jobs and stronger wages. Most established economists have thrown water on that theory.

That's because there's no guarantee companies would use their savings from lower corporate tax rates and repatriated foreign profits to create jobs. In fact, few CEOs have publicly made any such promise.

Markets are betting that companies would use their new spare cash to help investors: by purchasing boatloads of stock and beefing up their dividends. Both outcomes can help propel the soaring stock market to new heights, even if jobs and wages don't follow suit.

"The additional cash will definitely help buybacks," said Howard Silverblatt, senior index analyst at S&P Dow Jones Indices.

Investors love stock buybacks because they're less risky than investments in new projects that may or may not work. Even better, buybacks make earnings per share, a key measure of profitability, instantly look better simply by reducing the number of shares in the ratio. Underlying profits don't even need to improve.