I fight looneys with looniness.
If I sense someone is going to act crazy, I start singing the "MEOW MIX" song over and over again. But I don't sing the lyrics, I sing MEOW MEOW MEOW MEOW repeatedly.
That generally scares them into thinking I am crazy ordering a lot of alcohol and passing out.
It also gets much of the cabin to do the same.
(I also ahve scared away chatty co-workers who want to hang around where I work gossip. I work for a news station, not the National Enquirer!)
I have not figured out what I should do if I get an attractive Single FEMALE looney.