Well, Grilling must be nice if your on a boat... but I'm a bank fisherman. When I stay overnight on a river or lake, I pack BBQ chips, granola bars, candy, sandwiches, and whatever other snacks I may need. Sweet & Salty are good for satisfying your taste buds, but make sure you get some carbohydrates so you feel full. I hike to my spots, so I try to take into account how much I need and how much I can carry. Beverages are heavy, and they don't last long. I usually just strap a gallon or half gallon water jug to my backpack (depending on how many hours I'll be out)
Also, if your not too prude about what you eat, try eating some of the local vegetation and marine life. I've been known to have campfires when I'm fishing channels, and sometimes I catch some crayfish and cook em over the fire for a tasty treat. Bluegills also are an OK snack from what I hear. .. and cooking crayfish and baitfish is quick and easy compared to cooking and cleaning a cat.
hope this helps (somewhat)
This gave me an idea for a thread..