Excellent question. First off mfg'er's generally are really no different than many of the enthusiasts interested in their products.Seems like there is a huge oversaturation of brands in the audio market. Many companies like to take their products to shows, but the sound there is so mediocre, that no one really stands out.
And most dealer set up are not that great either.
What can manufacturers do to demo their products - so people are blown away with their sound and get people to crave it?
I can think of a few things right off the bat that could put an exhibitor's sound head and shoulders over many.
1. Employ superior (as opposed to none or inferior) passive, dedicated, and bi-directional filering line conditioners for each component.
2. Many hotel room have a single dedicated 20 amp circuit so whatever an exhibitor intends to demonstrate including associated lighting, when added up, should not exceed 18-20 amps. At the very least dynamics will suffer. And if digital is used, all the more important that passive, dedicated, and bi-direcitonal filtering line conditioners be used - lest the bi-directional digital noise induces its harm on every other piece of gear.
3. Speaker placement.
4. Ensure every cable and component is at least 4 - 6 inches off the carpet.
5. Ensure every cable, fuse, AC plug, IEC connector, and inlet is cryo-treated using the superior full-immersion method.
6. Always play music that challenges the system's limits including volume levels closer to the perceived live performance volume levels.
Assuming the products being exhibited are reasonable or better, these strategies are perhaps the best assurance that the exhibitor is putting their best foot forward for maximum muiscality in a make-shift listening environment. And compared to how little effort some exhibitors put into their display, these alone just might be enough to "blow away" the casual listener compared to many other rooms.
Then again, these are universal best practices for all - not just exhibitors at shows.