I don't really blame people for taking advantage of these (I bought a couple myself), but your strawman is pretty absurb. You'd have to be living under a rock to not realize these were mistake fares. I was messing around with Google flights on Thursday morning when these fares started popping up and I was sure it was due to something broke at Google and was wondering how long it would take to fix. Sure they were published everywhere, but that's how the GDS works. I was never under any illusion that DL actually meant to publish these rather than someone at DL making a big, big (possibly career ending) mistake.