Yes - it is due to the "fare sale". Even if you do not ask for it specifically, as long as the "fare sale" seats are available, whenever someone asks for an adult fare, you will get the "reduced fare" price! BUT NOTE - this fare is NON-REFUNDABLE! (But if you requested another fare like AAA, it would be.) True, you could apply the fare to a new ticket, but maybe the AAA fare would be in the 3rd or 4th bucket at that time.

BTW - 2 city pairs listed are CHI-ALB and CHI-NYP, so I would assume CHI-BUF is also included.