That's not why Fat Bastard shut the beaches down. That happened pre-"COVID" (July 2017), and it was about a budget fight going on in the NJ State legislature at the time.
"A social media storm is blowing around New Jersey Governor Chris Christie after photos showed him appearing to relax on a state beach with his family on Sunday. A few days earlier, Christie had closed the state’s beaches and parks to the public after hitting a deadlock over budget allocation."
https://time.com/4843444/chris-christie-beach-photos-shutdown-new-jersey/
Fact remains he shut down access for everyone else while he and his family enjoyed a day at the beach.
Regardless of the reason, in that case a budget battle, it shows his absolute gall that he would avail himself of beaches he closed to the very people who own them.