It's both!
If you want, but you'll probably be pretty uncomfortable. Both the bride and the groom will be wearing bathing suits and we encourage you to be as comfortable as possible.
Start with a blanket and go from there. Tents are technically not allowed (though you will see them with no issues. Umbrellas are just fine though. Bring beach chairs if that's your thing. Don't forget anything you'll want to play with on the beach, frisbees, balls, shovels, pails, etc. A cooler is a good idea too for snacks and drinks.
Why would you even put that out in the universe? But in that case, we will wait for it to break to set up later in the day and the ceremony would be after the lifeguards are off for the day at 6:00. Worst case scenario, we will push until Sunday same time, same channel.
Drinking alcohol is illegal in all public spaces in New York City including beaches. With that out of the way, remember to obey the uneasy truce. Put your can in a koozie or pour your drink in a reusable cup and stash your empties. Don't rub anyone's face in anything and you'll be left alone. You can also head up to Rippers or any of the other beach bars to enjoy a beer, beach juice (frozen sangria) or michelada and chill on the deck if defying local ordinances isn't your thing. You'll also most likely see people selling nutcrackers on the beach.
A nutcracker is a drink or dubious origin and multiple recipes sold in a plastic container right on the beach or at other events in the city. Typically, they will be a type of hard liquor mixed with a sugary juice like fruit punch. You'll likely hear the regular call "Cold Beer! Nutcrackers!" and they'll typically run you between $10 and $20. Want one but not hearing the call? You can DM @the_beachtender and let them know your location and they will deliver their finely crafted cocktails.