We saw this unusual boat at Kingman marine in Red Hook harbor (on Cape Cod) a few years ago. My first reaction was "what the h***?" but then I started thinking of it from the point of view of imagining what the owner might have been thinking: Seriously into fishing, but not in a rush to get to/from the fishing grounds (which are nearby -- the fishing is fantastic in the Cape Cod area) and save $$$ on fuel. This makes sense.
BTW the mods were done first-class. The fit and finish of the rails and fiberglass hard top are outstanding and the hard top even has recessed lights. Notice how the rails are custom made to fit the coolers. The tuna tower with remote steering and engine controls? OK that's literally "over the top".