According to the 2004 Florida Statutes

2004 Florida Statutes 161.54  Definitions:

(3)  "Beach" means the zone of unconsolidated material that extends landward from the mean low-water line to the place where there is marked change in material or physiographic form, or to the line of permanent vegetation, usually the effective limit of storm waves. "Beach" is alternatively termed "shore."

Summary: 

Area B/C = The wet sand area of a beach is land held in trust by the state for all people (Reference). This land, according to the above definition, is part of the 'beach'  that is publicly owned

Area A/B = The dry sand area of a beach can be privately or publicly owned

Area A/C = The wet & dry areas combined, the area known as 'The Beach'

Please consult a land attorney for clarification on land ownership

Personally, I think it's capitalism taken ad absurdum. How can anyone claim they "own the beach" up to the shoreline, and keep people from walking across "their property"?

So in the interest of one or two people, many others don't have the joy of taking walks along the beach?

I wonder why there hasn't been more of an uproar.  After all, especially when you look through personals, long beachwalks and sunsets are favorite activities of almost everyone.

Of course, people should be able to take hour-long walks along the beach, without encountering fences (or orange cones). The law supports this. As it turns out, at least here in Florida, you don't own the beach up to the water, even if you own beachfront property. I read a very interesting (and reassuring) article in the Destin Log dealing with these issues.

The Destin Log did an outstanding job digging out the details, so I took the liberty to post some excerpts here. I think these important facts aren't known enough, and the more people are ignorant about the law, the more the feeling will propagate that someone can buy a piece of the beach and disallow the public from walking along the shoreline.

Here's an excerpt from the article:

"During the ongoing beach debates, a common refrain from some Gulf-front owners is: 'I own to the water's edge.'

Florida State University College of Law professor Donna Christie said some deeds do purport to give the owner of beachfront property title to the water's edge. 'The state Constitution does trump the language in those deeds,' Christie said about language in the constitution reserving the shoreline as sovereign land. 'Basic property law holds that you can't sell more than you own. And the water seaward of the mean high tide line is held by the state in trust for the public.'