I really have no idea what you're getting so worked up about. If anyone wants to buy the Topaz plugins, they can do it through his site. They win, because the discount is greater than obtainable elsewhere (presumably); he wins, because he gets a commission; and Topaz wins (again, presumably, but otherwise they wouldn't bother with the affiliate programme) by selling more copies of their software.
It is not comparable to commercial advertising. Sometimes purism can overtake reality, and this is one of those times. Use of hyperbole such as "prostituting your members" is silly, unhelpful and leads inevitably to comments about arousal.
I shall continue to exercise my discretion as I see fit. Thus far, my intellect has not been taxed.
Jeremy