They don’t fly on dates 2PM and 8PM on Friday are the same dates but the former flight requires taking a leave from office, latter does not. 11PM on Friday and 1AM on the following Saturday are different dates for the airlines but it’s same for passengers. Discovery of the latter is especially poor on most booking websites.
Destinations matter more than the airport The concept of the nearby airport based on the distance is archaic. For example, San Jose (SJC) and San Francisco (SFO) are almost identical for most leisure travelers since most individuals flying into either are going into SF bay area. A bit further one from SFO is SCK (Stockton) which sucks for the lack of ease of connectivity back into the SF bay area. A leisure traveler flying into Kona in Hawaii might gladly take a flight out of Hilo which is on the other side of the island. While I am giving the example of airports I am more familiar with, I think the idea applies to most metros with multiple airports. Airlines treat such a ticket as open-jaw and usually charge a higher price.
The concept of the nearby airport based on the distance is archaic. Most individuals flying into SFO are going into SF bay area. So, SJC (San Jose) will work but SCK (Stockton) will suck.
On one occasion, the flight to SFO was overbooked and the next one was 3 hours later. The airline company was looking for someone to volunteer for the later flight. I asked if I can get the flight to SJC departing in 30 minutes, the boarding agent bluntly told me that I would have to pay 200$ for the destination change. Which of course, I had no interest in. That flight to SFO actually went with three seats vacant since the family of four preferred to fly together on the flight 3 hours later.
Long layovers might not be that bad 1-hour layover is good. 4 hours is not. But 8 hours or more might be a chance to explore another city. Airlines usually only inform you about the next flight which usually is 3-4 hours later. But if the person is at an intermediate destination, they might be willing to check that one out for a long enough break. Of course, airlines might never know unless they ask the passengers.
Reschedule in advance and not at the airport I have already returned my rental car, gone through pat downs, my bag has been investigated for the product, and an announcer has been repeatedly shouting “Looking for passenger Sukhdev Singh Chatwal” in a funny American accent. In these conditions, you are asking me to if I would take the later flight for a 200$ voucher. Never mind that the voucher comes with “conditions apply” and has an expiry. No, I am not going to volunteer my ticket. It is not that an hour before departure the airlines learned that the flight is overbooked, they probably knew about that many hours or probably days in advance. Then why not contact me in the morning when I was swimming in Culebra? In fact, the most likely reason for booking this earlier flight was because it was way less expensive than the more desirable flight which you are offering me now. Being at the airport, it is too late for me to make any use of that time.
I have already returned my rental car, gone through pat downs, my bag has been investigated for the product, and an announcer has been repeatedly shouting “Looking for passenger Sukhdev Singh Chatwal” in a funny American accent. In these conditions, you are asking me to if I would take a later flight for a 200$ voucher. No thanks.
Consider rescheduling earlier (" prepone") Leisure travelers trade-off minor inconvenience for money. If the flight at 1AM is less expensive than one at 11PM then many are going to choose the first. Even if that comes with a tight layover. If on that day, the earlier one is going vacant then why not inform passengers of the 1AM flight in advance? Many might gladly take the offer of flying earlier.
For the big three airlines (United, Delta, and American), the primary source of revenue is customers traveling for business. These customers usually cannot reschedule earlier, they are not looking for the long layovers, and airport codes matter a lot to them since their rental car booking is most likely tied to that. But that’s exactly why leisure travelers should matter, they are flexible and are willing to adjust for a win-win situation.