I would have included the Belfast Co-op but didn't want to appear overly chauvinistic.

Actually, there are several places along the ICW where you can walk to a Publix supermarket. We're at one now at Cocoa Beach. Two bridges to the south, there's another near Dragon Point. And of course the one at the north end of Lake Worth is a very popular one for stocking up for the Bahamas. We find the Publix and Harris Teeter chains to be the best.