I can see the draw in wanting to pay so little to skip the SWU line and confirm the upgraded seat.

And, honestly, I'd never seen these cash upgrade offers before, and was tempted myself.

It's just that with no pretense of preference for upgrade instruments awarded for loyalty, it makes every interaction with the airline a one-off cash grab.

If the deal is that I'm a transaction and not a customer, than the whole idea of loyalty is a scam with no reward.