StubHub airlines

In a few weeks of making flight reservations for myself and others to various locations, some on short notice, it's become clear that the airlines are running the same game as concert ticket auction sites. Two days ago a round trip ticket that I needed was $441. I was kicking myself for having to pay this much for a relatively short flight, looking at the Southern Crescent with its terrible train schedule. I checked the airline again today---$213 for the same ticket. They obviously had some extra seats. Same with another ticket for someone else, a longer trip, $360 two weeks ago, $600 four days ago, $470 when the purchase had to be made today.

This is all legal, and the rationale is obvious. Fill the planes and get as much for each seat as possible based on some completely unstated pricing system run by mathematical models. This consumer can only scratch his head and keep checking prices until it may be too late.