The article implicitly assumes both that game developers only make games for the money, and that a front-loaded payment model is the only way to go; both of which are not necessarily true. For example, Tarn Adams (Dwarf Fortress) earns his living entirely through donations.
Fixed that for you. Tarn Adams is the only example of a game developer living entirely through donations. Not even Jason Rohrer, who lives a minimalist lifestyle in the middle of nowhere, is capable of sustaining himself on donation only income.
Compare that with the overwhelming number of game developers who make a living through getting paid by people buying games.