Why make it that easy?
I have never understood why things are made super easy. Most people do not realise the risks and we cannot expect them to. Jewellery will be secured, a piece of paper? Yes, even now quite a few do not realise what that means.
So, Either make it not so easy (no QR code and all), Or preemptive actions and make people aware of the risks.
And, from exhausted experience, most do not realise until it is too late.