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, SC. The people who put it on tend to being almost exclusively sporty douchebags and suburban moms.
That's about it.
Edit: changed NC to SC
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, SC. The people who put it on tend to being almost exclusively sporty douchebags and suburban moms.
That's about it.
Edit: changed NC to SC