After thinking about it for quite some time, I tend to agree with the thinking that since we only have 24 hours to cancel or face a hefty penalty, it does seem only fair that United had 24 hours to cancel. I don't think they necessarily need to validate the tickets, but rather offer some sort of decent compensation, in just the same way that a consumer would have to pay a hefty cancellation fee.
Bottom line is that if United doesn't think it's fair that we get to travel at 4 miles with their booking process due to a mistake, then they now know how it feels when a consumer makes a mistake and has to pay a hefty fee because of it. $10 million to them is like $150 to a lot of us that are not rich.