Got a garden variety at-purchase upsell offer, figure I'll report it for data's sake as we need more "normal" results.
SFO-BUR, K fare.
Fare difference to P at booking: $143
Upsell offer: $99, declined (this is the route fare differential)
Inventory when offered: F8 A7 C8 D7 Z6 P5 PN5 R1 (booked 0/8 on a 319)
Expecting a CPU but will ride it out in row 7 if need be