You speak as if he's playing any role in that money doing useful work. He's not, he's sipping drinks by the pool, while millions are doing all the actual work. He just happens to have his name written on the paper. That money would do the same work no matter what the name is - or indeed, without any name on the label. That's what differentiates someone doing useful work (e.g. Elon Musk) from all the fancy-drink-sippers no matter what their names are.

Beyond a certain limit, ownership is bullshit. It's really stewardship, but it's forgotten its true limits and purpose.

When you're touching so many people and resources, you're a steward, not an owner, period. What's lacking now is a mechanism for the bad stewards to undergo corrective action.

I didn't claim he was playing a role in the management of any company, I merely claimed he wasn't holding money.

If you believe Piketty that the wealthy are better investors than the rest of us then the wealthy are actually doing useful work: directing resources towards their most productive use.

I specifically excluded SPY in the last paragraph as a "productive" investment, but only for the sake of argument -- I admit I'm inclined to agree with you that even passive investment of this type is productive.

I think the problem pointed out by the original article is that they don't like this because it tends to produce oligopolies (i.e., "chains"). Unfortunately, I think that's just because non-colluding oligopolies are efficient.

So the market is "working," some just don't like the outcome.

Buying someone else's shares of a public company isn't super productive. You're buying a stake in future cash flows at companies, not investing in growth. Especially the way buybacks have been going lately,

The cash one exchanges for shares of a public company is usually spent on paying wages, buying equipment, funding R&D etc, thus enabling future growth.

If one happens to invest into the inefficient company in a long term it is going to be bust along with investor.

How comes this is not productive?

When you buy a share of SPY you're not paying that cash to all the S&P 500 companies, you're paying it to another party that already has a share of SPY. IPOs give money to companies, but trading shares between parties does nothing for the company and contributes $0 to wages, equipment, R&D, etc.

I own shares of SPY, if I sell them to you what exactly changes?

Yes, the cash doesn't go directly from you to the company, but you're creating a market by which a company can raise funds through a stock offering.

Take away the market and the company wouldn't get any money.