Actually, I think that the rooms were not all that bad for sound, and certainly better than most people’s home listening spaces.
The rooms were actually quite large compared to a regular living room and set up symetrically. Speakers were typically well into the room and not placed along the wall nor was the seating. Most demoers had absorbant panels or such placed next to the speaker and many, around the room.
AND..., if you sat toward the front middle, there was no furniture to get in the way and create diffraction.