That also points to the uniting factor between the grift the article talks about and the traditional definition of the word: grifts are the strategies you use when other avenues of making money are difficult, say because your investors are demanding increasing returns from a saturated market.
This is exactly how Bernie Madoff was caught.
As for making money becoming difficult, without monetary and interest rate manipulations it would be rare for capital to exist while the opportunities to employ profitably are reduced. Capital is supposed to be created trough the act of saving, and income is normally saved with the idea of funding larger consumption in the future (or maintaining the same consumption with less labor).
That plan for future consumption is, in and of itself, an opportunity for profit to those that can satisfy it.