So would you get a ticket for being naked, or just for touching yourself? What about being naked with a hardon, but not doing anything else?
You won't get ticketed for simply being naked, no. There was a whole beach full of them that day. But you will (or can) get ticketed if you do anything sexual, such as masturbating, or more. This beach used to be a place you could go and do such things, exercising some discretion and common sense, and it was largely unpatrolled by the park rangers because no one really cared. But once the beach was redone and welcomed and attracted more than nude men, then the beach patrol became serious. You CAN still get a way with stuff, but you have to be much more careful.
I don't really blame the rangers. They are just doing their jobs. And frankly, now that others are using the beach besides nude men (such as women, children, families, toursits, etc.), then it probably isn't the right place to being doing that sorta stuff out in the open.