Calling people wearing these 'nonces' (pedophiles) regardless of truth or not. It worked with Google Glass before and it'll work again. Attach a stigma to it straight away to discourage uptake.
It's true you can already film people in public, sure, but covertly filming people is another level on from that.
Personally, I simply can't see any good reason to wear a camera or AI overlay on the face in a public area like this as opposed to just keeping it on the phone where it is now. As a glasses wearer, I'd rather not have anything on my face wherever possible, especially in a country with such bad weather. I can understand the technology in private hands-free settings and for filming action shots (like how GoPro are often used), a lifestyle which (sadly) most people do not possess.