Back in the day before mistake fares were blasted over social media, many carriers honored their mistakes largely because there tended to be relatively few tickets issued and the entire out-of-pocket and brand damage far exceeded the small number of tickets issued.
Now, when any number of social media types send out what amount to notices, the numbers move in the other direction. If the people who had originally made these purchases had not said anything, I warrant that they would be flying on those tickets.