Police officers could wear them to ensure good behaviour from the police and public alike.

You could modify them to include a range-finder so surveyors could look at a building or room and measure it, just by being there.

You could use them for virtual reality applications -- "weak" VR since not fully immersive but nice to check out the proposed make-over for your living room.

Sports-people could wear them to give first-person views of the action.

They could be worn to workplace disciplinary hearings (or any other low-level legal proceedings) with your representative/legal counsel listening in and offering feedback. You could record everything, so could your counsel.

There probably are thousands of applications, but compulsively recording public spaces and the people in them is probably not the best.

One example we all know well. Car mechanic. Parts analysed from the video in real time to provide contextual information e.g. replacement periods. Asking questions about stock information from the suppliers. Looking at VINs to instantly see warranty/recall information from the car company.

Now if I own a car mechanic business I could never build this. But Google has all the technology today that just needs pulling together into cohesive services.

But instead of solving these real world problems they instead prefer to get embroiled in consumer privacy issues.