Airlines have to pay a gate fee every time they use airport facilities, runways, gates, ground service crews, etc, easily into thousands of dollars.
There is also fuel costs for the flight that went nowhere, and the cost of another flight for all the other passengers.
The airline has probably banned him for life already. Hopefully they go after him for every penny he cost them.
I couldn't care less why he did it. He is an adult and ruined hundreds of people's holidays.
Just to be clear, fuck him, no compassion.