Originally Posted by
aubreyfromwheaton
someone on another page explained the rationale behind this as they don't care who buys the cheap seat, but without the cheap seats bought, the expensive seats cannot be sold, so it's like musical chairs, gotta fill the cheapies before raking in the cash.
Not at all true: they can set fares to increase over time, so anybody who buys at the last minute pays the high fare, whether or not any cheap fares were purchased. They aren't required to sell X number of cheap seats first.
However, they have an estimate of how many expensive seats they'll sell last-minute, so they
want to sell the rest of the plane as cheap seats in advance rather than letting them fly empty.