About the 1.5 points per $ spent... I don't know if it's available in the US or the rest of the world, but in Canada Gold Amex holders can pay CAD$50 for the Amex "Points Accelerator," and received 1.5 points per Canadian dollar spent. Canadian Platinum cardholders get this benefit for no extra charge. When converted to US dollars, it works out to more the 2.25 points per US dollar spent.
Based on today's exchange rate, that purchase would translate into CAD$3,843,207, and 5,764,810 Amex MR points. While airline ticket options in Canada using MR points have been significantly curtailed with the demise of Canadian Airlines, last year that would have gotten you at least 46 first class trips on BA from, for example, Vancouver to Cairo.
Having recently done that trip on a CP/BA award and priced it out on Travelocity at more that CAD$18,000, conceivably those MR points could've gotten you CAD$828,000 worth of flights. That works out to about USD$550,000, or 22% of the original transaction.
All this doesn't include other discounts and promotions that Amex and Canadian Airlines had, nor the 10% bonus that Platinum card holders received for the last half of last year. Geez, I miss CP...