I don't think scooters will ever be as big, here in the States, as they are in Europe and Asia for a couple of reasons.
1. In Europe, and more so in Asia, scooters (and motorcycles) are used as primary transport for a lot more of the people. They are treated as basic, economical, utilitarian machines. People there ride their scoots everyday, for all their daily transportation needs. And, they seem to keep their scoots and bikes longer, and ride them till the wheels fall off.
Plus, Europe and Asia, don't seem to have the same motorcycle snobbery that America has. At least, not as bad.
Here in the U.S., while there are a few of us who have forsaken the cager lifestyle, the overwhelming majority of American riders only see bikes of any kind as recreational vehicles. Fair weather play-toys! If it's warm and sunny outside, the bikes come out, and they ride like it's their whole life. As soon as it's a little chilly out, or there's a 5% chance that a drop of rain MIGHT fall, then the bikes and scoots are locked up in the garage and they run back to the comfort and protection of their cars and trucks. For that reason, most Americans only want the biggest, loudest, and most obnoxious ride they can get (Harley). And they seem to not keep them for very long, and trade them in every time the next new thing comes out.
2. In the States, we have virtually NO aftermarket support for scooters. So there's almost no options for customizing our rides. The only options for us is to either find connections with overseas parts makers, and pay a fortune for shipping costs, or to custom make our own mod parts. And as much as I hate to say it, MOST Americans are too freakin' lazy to put that much effort into it.
Look at just about any Harley Davidson. 99.99% of the "CUSTOM" Harleys out there, are nothing but a bunch of off-the-shelf parts that are just bolt on styling touches.
With most of our scoots, the only things available are some aftermarket windscreens, top cases for the back, and some performance mods for the folks dedicated enough to put the work into it.
For anything else, it's either DIY or don't do it at all!
If we had the same level of aftermarket support as motorcycles do, I think A LOT more Americans would take a more serious look at scooters.
3. Finally (and this is just my goofy brain at work), I think a lot of Americans don't ride scooters, because there is NO scooter on the market that says Harley Davidson on it!
If Harley designed, and built a motorscooter, there would be American buyers lined up out the door to buy one! Granted, half of them wouldn't start and the other half would spend more time broke down on the side of the road than actually being ridden, but American buyers would buy them, just because it would be something new and different from the "Mother Company".
But that's just my opinion!
Duke-
FYI-- Despite the way it sounds....NO, I don't have anything personal against Harley Davidson! I have MANY friends who are Harley guys. Harley was just the easiest, and most obvious example to use!