parking under my building in the Sydney CBD is ~$85 a day, and checking the Sydney airport website, a days parking is $105
$40 a day is a pittance
At LAX the economy lot is $12 a day. If you park at one of the FlyAways and take the bus it's $4 a day.
This isn't really meant to compete with economy parking though, it is? Parking nearer the terminal at LAX is apparently $30 a day.
Atlanta, the most I pay for parking would be at a sporting event or concert where it's usually around $20 for the event. The only $40 or more parking would be at the airport.
You do realise that the article is about a parking system at an airport?