Within an couple hours' drive of NYC, you can find lots of sleepy seaside towns. Not only can you get your soft ice cream and salt water taffy on, but you can still spot cool, hand-lettered signs and other relics of a past generation's amusements.
Having the experience of owning and running a coral reef aquarium (and frequenting this particular shop about once a week) - I was sad to hear it closed it's doors. Their reef display tank was always amazing. These pictures were taken from PetCo at Union Square (I also used to go there for my saltwater needs).