The opaqueness of QR codes for public uses like this is a problem. I was musing on this on a restaurant patio recently, that used the "QR code to view our menu" sticker things. It would be no work at all to slap new code stickers on all the outside tables. The potential for actual malice is maybe low there, but mischief is easy (ads for a competitor restaurant, PETA website at a BBQ place, autoplay fart noises, just general gross-out website, etc.)<p>I suppose the builtin Android and iOS code readers will have to get a confirmation step at some point. The classic problem of convenience vs. security.