I think it''s mainly just tradition -- ie., the way it''s always been. I have an inexpensive Garmin fishfinder
on my Cape Dory 26, and it works fine. I agree totally with you, the fishfinder
shows things like bottom status, etc., which can be useful to sailors. I asked the same question about a year ago, and decided to get a fishfinder
, and have not regretted it. Good luck and fair winds.