In Alaska on the way to The Homer Spit and many other areas there are some beaches that launching very close to this takes place.
BUT since the beaches are have very extreme tides, you bring your Boat and trailers to the shore line and disconnect, A farm tractor now takes your boat with all aboard and launches you. and places the trailer next to your car. till you return a simple call and the tractor returns to retrieve your boat . The trailers have very high guide posts on their rear so you know how and where the trailer is.
Honest. This also is because the water depth is at times afar form the beach. Most of The bay is like this. Bill