I would think that it depends on what part of the country you are in. Obviously, you cannot always predict where you will end up, but if you spend most of your time near the coast as opposed to the interior your gear should look different.

In salt water, a bait rig would be a great way to get many small fish. It has about 10 hooks prefabbed on line and feathers or beads as attractors.

Inland, your best bet is likely small trout in small streams or small pond bobber fishing. Line, hooks a bobber and maybe a bit of artificial bait or planning on using insects, grubs or worms.

Without a rod, I just don't see hooking and landing anything larger than 8" or so.

Outside of that, it is an excercise in passing time - like fishing is for me most of the time anyway.

For an offshore marine kit, fishing is a much bigger deal as one could spend quite a bit of time in a raft as history has shown and a fishing kit could easily make the difference between survival and the alternate.