I’ll copy my response to the other person who was also confused by the reference:
In America, there’s a very popular car windshield decal sticker that people put on that says “Salt Life.” It specifically just means someone visited a popular beach vacation spot called Myrtle Beach, NC. The people who put it on tend to being almost exclusively sporty douchebags and suburban moms.
That’s about it.
Huh, that’s somehow way worse. I always was under the impression that it was only Myrtle Beach.