I've been a "banker" too, since '63. Koz put it perfectly. In rivers, boaters just go anywhere. Well, almost. Me? I have to beat the brush and weeds, search for rocks in the mud, ask landowners' permission, avoid breaking my rod on the overhanging branches and lose lots of lures that I snag and can't get free. And yes, as Dirtyeggroll said, I gotta watch out for the poison ivy. The only place I'm on a nearly equal footing with boaters is right below the dams. In fact, I can fish some tailwaters much easier than a boatman can, especially around the rocks. That's why I have so many spoons; they survive the rocks much better than crankbaits.
As far as lakes go, I can access productive water somewhat easier, but boaters still have an advantage. (I'm learning to like lake fishing; I had been 90% river-oriented until the last year or so.) The one advantage I have in lakes is flooded timber. If the wind is against the boaters, I can throw a weightless Senko or jig under a slip bobber and pull stuff out that the boaters can't reach. That doesn't happen very often, though.
The last advantage boaters have is acquiring the fish. A bank fisherman has to deal with rocks and shallow water the last 8-10 feet before he can get a hand or net on the fish. I've lost a good few in that 8-10 feet. Boaters just lean over and scoop'em up.
Old habits die hard, though. I'll be a shorecaster 'til I die. jj