If enough people block the use of Glass, it could have an adverse effect on its sales and growth.
I figure it didn't take off for the same reason non-overly obese people don't use Rascal carts. People were worried about being perceived as lazy. They're also really expensive, so you'd be perceived as snobbish as well.
Just look at Gob's character in Arrested Development. They didn't stick him on a Segway because he's a prudent person that needs to get to places in a hurry.
It was expensive, large, you had to find somewhere to park it, you had to remember to charge it, it came with an aura of snobbishness (at that price tag, not entirely undeserved).
And it solved... what? In suburban America it doesn't go fast or far enough to get you anywhere in reasonable time. In urban America the distances people walk aren't worth all of the above compromises.
The Segway makes no sense to the suburbanite whose main mode of transportation involved their garage door opener. The Segway also makes no sense to the urbanite who can walk 100 feet to the closest grocery store.
It was a marvelously cool technology looking to solve a problem very few people actually had.
The segway solved nothing. It was a neat toy.
http://www.thebestpageintheuniverse.net/images/segsuck2.jpg
Source: http://www.thebestpageintheuniverse.net/c.cgi?u=segway_more_...