Doug Henwood quotes:

A rentier is an investor whose relationship to a company or enterprise is strictly limited to the ownership of financial wealth (such as stocks or bonds) and the receipt of income on that wealth (such as dividends or interest). The financial system performs dismally at its advertised task, that of efficiently directing society's savings towards their optimal investment pursuits. The system is stupefyingly expensive, gives terrible signals for the allocation of capital, and has surprisingly little to do with real investment.

Behind the abstraction known as 'the markets' lurks a set of institutions designed to maximize the wealth and power of the most privileged group of people in the world, the creditor-rentier class of the First World and their junior partners in the Third.

Instead of taxing rich people, governments borrow from them, and pay them interest for the privilege.