The use of “carny” or “carnival” to describe Coney and its atmosphere is common here in NY. Wish I had a buck for every time I’ve tried to explain the difference between a carnival and amusement park, or a carnival and a circus. People still didn’t get it or didn’t much care.
As for the NY Post, they are famous for lurid headlines like Headless Body in Topless Bar and Holy Shi-ite! They go for alliteration, rhyme and wordplay, so the “Coney” “Carny” combo is typical
The Post did have one Coney headline awhile ago that cracked me up---a zoning story called Coney Zoney Furor: Chicken King Clucks.