There are many reasons to buy paintings. Some buy for decor, some for investment, some as a gift, but those make up less than 5% of the total buyers. This means that the one who makes the call, comes over for an appointment to view a particular painting and ends up taking it home is a person who may or may not be into high priced art, they are most likely a person who see's a piece they simply have to have and cannot allow it to go to someone else. It expresses something they identify with and like buying a car or some other expensive item they find a means to acquire it. Payments are an option which some explore as a means to be able to own the one they love.
It's almost never about the money. It is almost always about the love.
On that note I have to say this is one of the most rewarding experiences for me as an artist. To see my work being sought after by someone who's heart has connected with mine through the paint I have applied to a canvas with some brushes. Someone who feels what I feel when looking at the scene. When experiencing the colour, the movement, the drama!
That's who buys a Robert McAffee painting.