Airports are stresful and noisey. Imagine how calming it would be with greenery all over the place absorbing the noise.
I guess it could be in some inaccessible way, greenery 20 feet up, or behind baracades with alarms.
But humanity is humanity, and part of airport security is probably the above.
(Also, according to a movie I watched, the next pandemic will come from plants, so we will have to kill them all, you see...)