I have Glass and one reason I don't wear it outside is discomfort from having strangers point or ask to try them on. I haven't encountered any threats so far (thankfully), but I try my best to be polite. I hoped the novelty would have worn out by now but it hasn't. I regret the purchase :(
That's just rude. Whatever happened to common decency? I would never walk up to someone and ask if I could try out their new iPhone or drive their interesting car.