Yeah looks fine. Probably goes out to community events and such like a radio station truck might. Banks/CUs aren't really the most interesting thing...
I would guess this is a security vehicle? I've never seen green on an airport vehicle, seems like most Fire or Airport Operations vehicles I've seen...
I would guess it has something to with putting it out before they get there when crews are working at a manhole. Not sure. I guess it's their manhole...