First of all the highway analogy is weak at best. FYI, there is a governmental process where citizens can be heard regarding the regulation of speed on all roadways.
Seems we always fall back to chicken and egg arguments. I would have to believe that the rights of the property owners were established well before Joe **** the Rag man Sailor of fine Derelict Yachts drops anchor and squats behind someone's newly constructed, multi-million dollar investment that he or she pays very high property taxes.
The issue is length of stay. When do you wear out your welcome? As a regularly cruising sailor who is responsible, I don't tend to stay at anchor in any one place for more than a couple of days. If I did, I would be "Anchoring", not "Cruising." I don't think anyone is looking to make a sailor move his vessel into harms way. I do think they are trying to keep derelict vessels from littering, more than they already do, the Florida landscape.
Wonder how you would feel if someone set their pop up camper in the street in front of your home and decided to call it HOME?
Responsibility matters. Get the derelict issue under control....no one cares about cruising boats stopping for a reasonable time before they move on.