I agree that those who have the ability both (a) to pay the higher fares and (b) to influence the decision when there is another game in town are the holy grail and the ones that any FFP should seek to attract.

Presumably these fall into a few distinct groups:

1. The unambiguously rich - some of whom could also fly private jets, or indeed any other airline, motivated by comfort and schedule only - so why would the loyalty programme sway their decision - possibly on competitive non-stop routes?

2. The not quite as rich but self-funding, self-employed - where time is critical?

3. Senior managers with a generous corporate budget and discretion but non-stratospheric salaries (so that a business or first class family holiday from other travel is a powerful incentive).

Also you talk about the cash incentive - there's a cash incentive to buy "now" in a sale, but it's rare to find a situation where airlines offering comparable product and timing are that far apart in price, i.e., BRU-XXX-IAH is likely to be within 10% whether you're on AF/DL/KL or LH/UA/LX or indeed BA/AA.