[fredley]

No not at all! I'm just making a point that for a company that oversees an enormous proportion of all the user-uploaded images in the world could make a big impact with a relatively small extension to the processing they already do on uploaded photos. I'm not saying any blame is directed at Facebook. While a certain blame does lie with the airline industry, airline ticketing systems were designed and built way before the web and ubiquitous cameras. To change such a system is non-trivial, given that it operates in every(?) country in the World all the time, and is safety and security-critical.

Since there's no obvious single entity to blame (and even if there is, so what?), we should be working together to prevent and reduce attacks like this. Apart from anything, Facebook popping up a warning about a barcode would go a long way to making people realise that they contain easily readable, and potentially private information.

Also, given how well image classifiers work these days, how hard is it to do the same for photos of (physical) keys, bank cards, and other commonly posted things?