It's just like painting the outside of a house. It looks like they are rolling it on. The biggest problem would be humidity and the finish will be terrible, but it's most likely a short lease so nobody cares.
With the Vertical fin,It would be a matter of Months when the LE area starts peeling off.
I guess getting it painted in a hangar & under controlled Atmosphere would be expensive,so why spent.
I may not win often, but I damn well never lose!!!