I believe it is impossible to say at this point why people will chose to use Google Glass. While the chef for LA Food Truck says that is why he uses it, that doesn't mean everyone will use it for the same purposes. Google Glass seems to be useful in a variety of ways. It will have to become more mainstream before we find the best uses for it.
No, Google Glass will not mainly be used by people who wish to influence others, because it will be used by anyone who likes convenient technology. It is true that google glass can be used for marketing purposes, but it can also be used for many other conveniences, much like a smart phone can do.
Google Glass will be a flash in the pan. Newsflash: people hate glasses. People spend thousands of dollars to get Lasik surgery just so they can get rid of their glasses. Why would they then spend more money to get another pair of glasses?
Besides, it's not like Google Glass has any real advantages over a cell phone, anyways. It's a product that doesn't have a market.
Many different people will use the creation of Google glasses for things they wish to do. I do not believe that people are simply using these glasses to try to influence others by things that they are doing. Not everyone will have this mindset when it comes to actually using the glasses.