I used to work for a company that found hotel rooms for stranded passengers so I can tell you the airlines the best the can to avoid this.
People refuse to listen.
To be fair, O’Hare is too small. They could add another two runways easily and have the planes to fill them. O’Hare is surrounded by suburbs that have been fighting expansion since the 1960s. This is why O’Hare lost the “world’s busiest airport” title.
Chicago also is a major hub to United and a minor hub to American.
You have to understand airlines use the “Spoke” model for flights. You have to think of it like spokes on a wheel. They route everything through a “hub.” For instance, Delta has a main hub in Atlanta, NW had two major hubs in Detroit and Minneapolis and United has hubs in San Francisco and Denver. American in Dallas / Ft Worth.
What this means is, if the hub gets back up, people miss flights. THIS is the cause of problem. In Chicago, United and American asked people to delay flights if possible on Saturday. They said, there would be no fees if they changed. Few people took them up on this.
Airlines are NOT first come first serve. Suppose you’re on a 9am flight and it doesn’t go. But a later flight at 1pm does go. Well they don’t bump all those people off the 1pm flight and make room for the passengers that didn’t go at 9am. One exception is first class. They often will ask the 9am first class passengers that didn’t get to go, if they will take a regular seat on the 1pm flight, then bump those people off.
People expect things from airlines that aren’t going to happen. I worked at a hotel by O’Hare in 95. The plane broke down. They had one flight per day. They put the passengers up at our hotel on Monday. On Tuesday morning, the airline called me and said, “Mark, the plane won’t be fixed, tell everyone checking out to call the airline and that they shouldn’t bother checking out and coming to the airport. The airline paid for another day.”
I told all the guests, not ONE SINGLE ONE stayed. They all checked out and went to the airport, only to return a few hours later. Why? I don’t know. If the plane ain’t working, it ain’t working.
(In case anyone wonders, airlines pay for hotel rooms when it’s their fault. If it’s considered an “act of God,” they do not pay. Weather is an "act of God. Generally airlines pay for first class passengers regardless, as they do anything to keep first class business)
I still remember Carol the gate manager at Detroit. I was on the phone to her and I heard a customer yelling about the weather and the delays and how important he was. She finally got so frustrated she said, “Do you want to be late Mr Smith, or do you want to be THE late Mr Smith.” 