It's mostly a touristy article, but I know what you mean. The casinos employ 13 or 14k people at the moment ... so it is a large part of it's identity. Keesler AFB, shrimp & seafood industry, cruise lines, Dole, oil rigs & refineries, etc.
It's essentially a typical town that has a substantial casino district.
I would be offended by the article if I was Biloxian. I'm sure they're plenty of good folks there.