I have noticed that a lot (or most) flights that go down the east coast of Florida to PBI, FLL, or MIA take a track that goes parrallel to the coast, southbound, and inland northbound. Why do all those flights fly in such a tight area?
For example, most of DL's & Air Trans ATL-FLL flights come down and cross the beach south of JAX, flying along but just offshore until approach when they'll have to cross back over for the RWY 9L ILS. Northbound flights follow a track about 20 - 40 miles inland. Even USAir going to CLT, Northbound follows inland and southbound follows just offshore.
It seems like that's a narrow area for so many flights (ATL, CLT, all up the east coast). Are there "tracks" for Florida-bound flights just like they have for Atlantic crossings?