Depends on who you talk to. I think it is silly to run shallower than you can get on plane with an outboard, but guys in Texas insist it is necessary. If you are just jumping the occasional sandbar, I guess it doesn't hurt anything, but that often isn't the case. Prop scars on grass flats prove there is an ample supply of jokers who already go where they don't belong.
Ultimately, no matter how shallow it runs, you're gonna stick it. Then you get to get out and push that big heavy beast back to water where it can float. When you can run in 2" and it has a 400-500# motor squatting the transom, that can be a damn long way.
Also, the great thing about fishing back in the flats is that you don't have boats buzzing you. I resent the idea of some fool who doesn't have to sweat being able to run up on me in 6" of water. If they mount a tower on it to cruise the flats for fish, I would say lethal force was warranted.
On the other hand, the Texas guys say that their flats are too big to drive around (How big are they?). Soooo big that if you done took off to drive around them, you'd eventually hit the beach in San Diego (No chit, my second cousin's buddy's friend did it in his Ranger). Since I would never, ever dream of accusing a Texan of exaggerating the size of anything, this must be true.
Do you really wonder? Humans in Florida would be skittish if there were 20 million gators running around. Florida is over populated with people and boats- its why I moved - AND. That is why the fish are skittish.