America is so car-dominated that it's hard for this to catch on. If our cities had 10x the population and fewer parking spots (because space is at a premium), we would be doing the same.
In fact, we probably will get there within 20 years. I can't wait for a Tesla ultralight EV or motorcycle. But you'll see this first in Chungking or Mumbai.
Why the hell did I move here? Bbecause there are no better towns in the south east - it's wrong, everywhere
Most of these trips are relatively short, somewhere around 5 to 20 minutes. Nobody is touring on a scooter.
The Segway form factor is remarkably maneuverable and space efficient for one person. But it's not $3k better than a bicycle or cheapo electric scooter. People are also familiar with riding bicycles, so there's no learning curve for scooters.
It's also hard to do this on a Segway: http://starburst.hackerfriendly.com/wp-content/uploads/2012/...
Dean Kamen might have said, if you live in the future, you won't drive short distances. He built Segway.