I agree. We used to have a problem with a canadian (he knows who he is, and since he has gotten much better I won't name him) posting almost daily about his commercial systems.
he thought $3500 for a bookPC was a good deal, and kept trying to argue with everybody who knew where to get the components for less than $750.
I sell systems, but I dont post ad's here for the pure and simple fact that I know that you know where to get the stuff and build it yourself. (BTW, I charge anywhere from $400-$2000 over cost for my systems)