I am a pretty basic eater and catching fish and my huge store of tinned fruit and cereal kept me in pretty good shape. Being a singlehander I was invited to dinner on more occassions than I would like to admit - I did try to keep a good stock of wine for such occassions, or chip in with something I had. It turned out he was the owner of a liquor distribution company in Florida. In the Bahamas, major food supply is really only available in Freeport, Nassau, Eluethera and Georgetown on Long Island. You spend quite a bit too for water or juice, juice more frequently as water is hard to come by in the Bahamas.
Taps are a rare thing in the Out Islands.
Most of the water I used for washiing clothes and drinking came from water wells that are surprisingly common on some of the islands of the Bahamas. I managed to sail about half of the trip on the Waterway both ways. Once I left Florida I ran my engine once a week for 15 minutes to keep it lubricated. My single cylinder diesel would run for 8 hours at 4.25 knots on one gallon of diesel. There are all sorts of ways to make money while cruising.