"Revenue-based" by itself (or applied to "program") is an ambiguous term. You have to specify which aspect(s) of the program are or aren't "revenue-based". Southwest has revenue-based redemption, the legacy US3 airlines only have revenue-based earning of redeemable miles (and not even that in all cases) plus a spend requirement on earning status. So there is no such one thing as "revenue-based", it covers a wide array of scenarios.