A few years back, I use to participate as a vendor at those type of computer shows. Was great fast cash (and awesome profits). If you think they are not making money, think again.
Word of WARNING to everyone. Be VERY VERY leary about super cheap prices on name brand software such as Microsoft Office, VISTA, or any other typically high dollar software that generally exceeds several hundered dollars.
At computer shows, you will find 3 types of software, Authentic, OEM and Fake
Authentic is what you find on the shelves in the stores and the prices will be really close to that of any store
OEM is software that would normally get shipped with a new computer. How this works is, a computer maker goes to Microsoft and buys 10,000 copys of say MS Office Basic. He sells 5,000 computers, but the buyers don't want the software. So he is stuck with 5,000 copies of software which the Computer maker then turns around and dumps on a wholesaler. This is how you find really good and cheap software at great prices ($50 to 75 for MS Office Basic)
Fake (aka pirated) is where someone has gotten a ton of CD's and just burned several hundered copies. The packaging is typically cheap (to non-existant). Avoid this software, not only is it illegal, once it's figured out, you don't get support and your just out of the cash you spent on it. Also, know that if you had bought it for a business you own, you are putting yourself at risk for fines and penalties that can run as high as $100,000 per software item. It is just not worth it.
If you want good software and you have local computer shows to attend, look for either of the first two, Authentic or OEM (which is also authentic, just a heck of a lot cheaper).
Good Luck to all,