Edited to comply with rule 7

I'll give you a hint and it starts in 1928 when Hotel owners in Atlantic City getting complaints from white visitors

“The matter of colored bathers was taken up,” an executive from the Ambassador Hotel wrote a public official according to historical archives at the Atlantic City Free Public Library. “The Georgia Avenue side of the Convention Hall would be a logical place for colored bath houses.” This led to the founding of Chicken Bone Beach. Prior to this Black and White people were permitted to occupy the same beaches for 80 years. James A. Bradley, the founder of Asbury Park, followed suit shortly thereafter. He also banned Black visitors from using the boardwalk until 10:30pm.
https://www.nj.com/atlantic/2019/07/nj-beach-was-the-only-one-that-allowed-black-tourists-but-they-made-it-a-hip-place-to-be.html

Then, in the 1930s NJ beaches started to adopt Beach Tags which became further enforced in the 1970s as a way to favor locals and keep out outsiders, you can probably guess who they considered outsiders in rich white beach towns, PoC, the poor, and people from the cities. They created policies that made beach tags harder to obtain and established parking time limits. And those same communities are effectively still just protecting that 1970s enforcement today.This paper from a researcher at Monmouth Uni, takes a long in-depth look at the privatization of NJ beaches.
https://www.monmouth.edu/uci/documents/2020/09/free-but-for-a-fee-addressing-racially-discriminatory-burdens-on-new-jersey-beaches.pdf/