I do drive with Glass on, but it is generally sleeping, unless I am asking for directions to a new place. As for restaurants and the like, I feel like there generally is no need for me to wear it, as it just brings up uncomfortable feelings in those around me, and it's easier to just leave it in the car.
Where Glass really shines is in the great outdoors. When I'm taking a walk through my history-filled city, or out playing with my kids, this is where I use Glass the most. Not having to take myself out of the situation to pull my phone out to take a photo, or get a quick snippet of info about a nearby point of interest are the killer features for me.
You could use them to get directions, or to dictate a text message while driving, which would be much less distracting then touching a GPS or a phone.
One of the best use cases is already banned by Google - face recognition. I sometimes forget a person's name, and it would be much less awkward if I could press a button and compare the face I see with people I've emailed with. It wouldn't be such a big leap - I already use tech in that case.. but it's much more conspicuous to pull out your phone and to search old mails or facebook to find out if it is "Anne" or "Anna" or "Tom" or "Tim".
Is it realistic to believe that they can enforce this "ban", in the long term?