From a 'pure press' perspective:
I have often noticed that the rooms that get the press are the ones with the best sound, and not necessarily the best price. Just as in boxing , the bantam-weight boxer gets no credit for going against a heavyweight. Many rooms have personally bragged to me about having super-cheap cables or a low-cost low-powered amp, yet somehow, the bottom line is still the sound; and if that room's sound is not as good as it can be, it gets burried beneath the raves of sound of other systems.
From a 'end-user looking for nice equipment' perspective:
Many end-users rarely note the price of accessories such as cables and power devices. I often have seen rooms that brag about affordable components while running off cables and power devices which dwarf the cost of the system.
As sad as it may seem, even those systems pointed out by JosephAudio would not have qualified for the "sub-$10,000 systems section" suggested by Hgeifman above. In fact, I think that the only system I recall seeing at the show that qualified was the Onkyo room (and, not surprisingly, it was not a 'best sound at show' room, nor have I seen much press on it).
Bottom line is that if you are a boutique audio company with a cool product/component that doesn't cost a whole, you would still have the overwhelming temptation to be exhibited with a system that showed off your component in the best light (cost no object).
When you consider how expensive it is for exhibitors to show ($10,000 - $20,000), the incentives may just not be apparent to do otherwise.