Of course nobody wants to buy software from a kiosk in the middle of a CompUSA. Remember the reason they're coming into CompUSA or wherever to begin with? These are the fucking idiots who can't figure out how to set up their e-mail or install a program. They're the ones who called you and said "I just bought such-and-such a computer" and then read off the feature list to you from the side of the box. "Is that a good one?"
Who's going to go into a store and then order something off a computer in the store? They could have ordered the software off the internet at home, if they had any sense. They come into the store because they haven't figured out the whole internet/digital thing yet. Their universe is made up of bricks and mortar, concrete and glass, wood and plastic. The concept of access to the world via GUI is simply way too much for them, too intangible and nebulous.
Figure it out, SoftwareToGo. Virtual sales in a brick-and-mortar store is far too incongruous for the ilk of people who are likely to venture there.