The only reason anybody drives on the beach here is because they don't give a damn about the beach, or the area, or the locals, or the future of this place.
Ask the locals (who don't live in the 5 million dollar homes): Only jerks drive on the beach.
If one is too impossibly morbidly obese to carry one's own crap or self down to the beach, one should have one's kids drag one's bloated carcass out of the H2 and into a wheelbarrow for the brief journey to the water's edge.
You're potentially driving on endangered turtle nests, and even beach cops have been known to crush human sun bathers to death (another locale, but it could happen here all too easily) while rampaging down the beach in their 4x4.
Every time I see that beach drive sticker on a car down here I think to myself, I think, "There's another selfish navel-gazing twit who cares more about his own fat pasty white ass than anything else in the world."
And then I might get even more pissed and say something like
"OH MIGHTY ODIN, WHERE IS THY CLEANSING THUNDERBOLT! NEPTUNE! RELEASE THE KRAAKEN!" And then I would imagine a giant gamera-like seamonster rising from the swirling, vengeful gulf and smashing the poo poo out of some stupid SUV and everybody in it, and maybe taking down that ugly-assed, dooky-orange color new holiday fish inn between blue mountain and grayton in the aquatic maelstrom.
Seriously, unless you are elderly or disabled, you have no legitimate excuse to be driving on the beach. If you really love this area, then use your feet, stay off the dunes, and give the beach the space, care, and love it needs to flourish. The odds are stacked against us like the chips against a burned steak.
Only you can prevent beach assholism.