This place does seem to be uniformly wealthy, almost antiseptically so since Sandy destroyed the place and so the rebuilt mansions are all of the same vintage. That said, you still have the servants who live in the maid's room or suites, or above the garage.
Yes, I found the place sterile and loathsome. The vibe is it's for a bunch of investment bankers who skipped taking any humanities courses, hate paying taxes, and intimately know the ins and outs of the carried interest loophole. There might be a few math nerds mixed in who write algorithms for instant computer securities' trades to exploit perceived inefficiencies in the market. That is a "thing" now. Eww!
Oh the beach is all closed off its entire length to the public as well. Zero parking, and almost no beach access easements. You are just not wanted. Go to Coney Island if you want to get wet.
Deal, NJ? Sounds like the perfect name for a place for investment bankers and math nerds to live.
There are plenty of places where, due to zoning, are uniformly rich, particularly, as others have said, in the Northeast. When even the “slums” of the town are upper middle class, you know you’re in one of these places.