Having been at the Production Show 2004 all week demoing equipment to potential purchasers (as well as crowds of students on day-release from meeja skool!) I conclude there are two types of people who witness demos and to a degree their reactions probably mirror their overall views of life:

• The enthusiast is either impressed or easily impressed by cool technology - they really get into the demo and have loads of insightful questions - they want to understand how it works and fits into what they do.
  
• The cynic takes a pride in never being impressed - they can't in any way see how anyone could have a use for the software/hardware you're showing and a minor option missing is the most important thing in the world to them. I used to work for a guy who I was embarassed to go to trade shows with for exactly this reason and that lack of joi de vive was mirrored in every other area of his life.