One main reason for the lack of baitcasters in southern estuaries is that the lures used are usually light weight and downsized compared to the north. If you using a 16th ounce jighead on a baitcaster you won't get far. This means threadline reels are more versatile. Saying this though there are still alot of fish that are prepared to have a go at larger lures but IMO downsizing lures is a nessesity in highly populated areas therefore making threadlines more effective due to casting distance. Also because I am landbased, baitcasters are not viable when flicking in tight country for bass etc. from the bank....it can be done though.
Pete.