Because essentially, since the dawn of cities, cities have been about shopping. You don't need a whole set of roads if you don't have shopping malls. You don't have afternoon rush hours bigger than morning rush hours because of shopping. If it's a 10 percent revolution, then it's just another sales channel, and no big deal. The problem is it all depends on human sociology.
Sociology beats technology every time.
But sociology changes. For example, if you look at car sales, almost everybody who is connected to the Internet does a little research before they go off and buy a car. But almost nobody buys a car off the Internet. The reason is, I was told by my father, that you have to go out and kick the tires, or take a test drive. Maybe my sons, who are used to downloading Sony racing games, will be willing to download a simulator, run a Jaguar around a track, crash it in cyberspace and learn more about that car than I ever will by taking a ride.