Ed,
There are probably a few reasons why bass rods are relatively short. I think the primary reason is that they're made for specific uses. Flippin sticks are longer cause you need to whip the lure out there with little effort. Saltwater rods are mostly designed for fish fighting (tuna sticks, trolling rods etc. not counting jigsticks and some plastics rods) while bass rods are designed to pick up on slight taps and being able to feel what the lure's doing all the time. Shorter rods are probably more sensitive for that kinda stuff. That's an interesting question though, maybe I'll post it on ncbf.com and see what some guys have to say. I know there's a couple saltwater guys that can compare.
-Brian