Yeah...I'm not sure how you "fake" a fishing show. You can certainly edit it to cut out all the dinkers they catch and only show the bigger fish, but I wouldn't call that "fake"...unless they have scuba divers down there hooking the fish on. And I'm sure Bill Dance fishes on what mostly seems like private (well stocked) ponds and lakes...again, not really faked, just trying to make for good tv...
I always just assume anything called a "reality show" is automatically not real...
edit: and I've never thought of River Monsters as a reality show...more of an entertainment/documentary type of show...