I would consider all passive investing rent seeking. Or at the very least a kind of rent.

Just a quote from an article that sort of illustrates the attitude I have towards it:

> One disturbing implication of Thomas Piketty’s new book, Capital, is that the American economy is slipping into a form of “rentier” capitalism, in which passive income from wealth, increasingly in the form of inherited fortunes, is supplanting dynamism, hard work and innovation. - https://qz.com/196575/to-get-rich-forget-entrepreneurship-an...

Apparently I'm not the only person with this attitude, although this poster was down-voted: https://news.ycombinator.com/item?id=13151809

There's also some links there. I do use passive investing, but I do consider it a kind of rent and I think society might be better off with less of it.