I can see the point don't know if Glass will make it however it used to be EXTREMELY weird to see people with bluetooth headsets and even more odd if people were talking on them in public places "Are you talking to me?" now it's so normal for the most part I don't even notice them.
That's because people now use wired headphone/mic headsets for the most part (and occasionally bluetooth stereo headphones with mic as well) so the users just look like iPod listeners.