Wow, I have wondered about this as well. I have a question though. I'm about 20 min from DTW. I'm trying to book a flight back home to LAX , leaving sun (7/1) or mon (7/2). Would it be possible to get these savings when buying a ticket a few days in advance or must i simply show up the day I wish to leave and purchase the ticket then? i was about to book online when i noticed that "lower fares at airport" bit. Please advise.