Perhaps that's because Walton County doesn't have an evacuation plan. No one has done the math.
The state does the math. I believe it is the Division of Emergency Management. All this stuff is on line if you care to dig it out of the state web sites. Don't know how current it is, though. Last I heard the clearance time was 20 plus hours, and that was before the real estate boom.
The County EOC does have a hurricane plan. You can call them up and get this info too.
Mind you, I am not saying the plan is any good, but it isn't accurate to say nobody has done the math, etc.
Best thing to do is make your own plan. Wherever you are.
Anyway it is apples and oranges. We need a new bridge for safety and traffic flow, with or without hurricanes, and with or without casinos. IMHO, if the county had been doing its job the last 10 or 15 years, we would already have a four-lane bridge.