Right, it would be silly to carry around a spare pair of glasses just so I could take off the Google Glass in ... well ... every situation where I'd interact with people.
So my option is still, don't buy Google Glass. Problem solved. :)
I think of them, the way I think of the video cameras I own. They sit on a shelf charging. When I need them, I use them at the event. When I'm done with them, I put them away. There's no good reason for me to keep the camera up and facing people I didn't intend to film.
I know people love using the "but my cell phone can record video!" excuse. The problem with that excuse is, you aren't holding it up facing them the whole time.
So yes, I won't own Google Glass, because it's simply going to piss people off. Problem solved.
I can think of a few reasons I might want them, but the cost and annoyance problems are still there. The only good reason I can think of to wear them is that I could have the camera in place. I can get a GoPro or whatever for those circumstances. Like, when I was driving car races, I went through some trouble mounting up a camera in the car. That was before GoPro was a thing, and duct taping a video camera to the side of my helmet wasn't really a practical option. :) Even still, if I got Google Glass to do that, there would be too many negative side effects. The last thing I want during a race is for an alert to come up in my vision with an email, facebook post, or phone call.
Come to think of it, the last thing I want to happen while I'm driving normally is for any of those alerts coming into my vision. I leave my phone in a suction cup holder on my windshield. I have the option of glancing over to see who the call is, when I've determined if it's safe (i.e., I've already stopped driving).
Somehow, I can't see any good reason to have Google Glass, except when I'm sitting on my couch waiting for a call or to do something online. I already have a lovely PC for that, and the screen is much larger than their monocle.