For the most part, Florida residents face the same obstacles the rest of us do in having to plan well ahead to get a chance at campsites. Residents do have one big advantage though, in that they are in position to take advantage of last minute cancellations that are not practical for out of staters to use.
There is this though, the national forest service campground we're in right now has 86 full hookup RV sites. A tour through the park last week found 47 of those sites occupied by vehicles with Florida plates. Our previous state park also had a high concentration of Florida plates, although I didn't do an actual count there. So apparently a significant number of Florida residents are managing to get sites it seems. If Florida residents demand site availability at will, then the only answer it seems, would be to drive out all out of state campers so empty sites will be there when and where they want them. Of course that won't happen, in part because Floridians would then crowd the parks themselves, resulting in the same problem as now. In the mean time of course, all the rest of us would have moved on, taking our out of state money with us.