people that have a lot of photos with QR codes would want it :).
You could search your images for qr codes that go to linkedin, ig, or fb pages. or find the qr code wifi passwords.
if you just have a screenshot of a QR code (like you zoomed in and screenshot the ticket's QR code, no other text), then finding the qr code by the event name could be useful.
Thailand requires qr codes that linked to the nutritional information registered online. this could be useful to help you search products that just show the back of the label and not the front of the product.