I would never go without a "fish finder".  They really aren't fish finder, but depth finders and structures finders.  Graphing fish and catching fish, at least for me, have a very small correlation.  Some shorelines drop off very fast and other very gradually.  You need to know if you are in 20 feet of water verses 60 feet of water.  If you are trolling, once you find how deep the fish are you can keep your lure in the proper zone.  Plus, sometimes, it just cool to know that you are in 200 feet of water.  I think Old Salt said without a fish finder, you are wishing-not fishing.