United doesn’t want to fly half-full planes. They’ll just force him to transfer in other cities
Yep. He'll likely have to fly to LAX first then to ORD.
Most people really don't realize some of the pretty thin margins the airlines operate on. These days if a plane isn't full / over-booked by 20% the airline loses money.
The airlines purposely over-book because they know a certain percentage will miss flights/re-book before their flight and don't want open seats.