Nope, which is why you need to take the precautions you are asking about. Something as simple as getting sea spray on the lens and then letting it dry can permanently damage the surface of the lens.

Get some of those plastic food bags and some rubber bands, make your own protective cover using these, the rubber bands make the body splash proof and sand proof.

Use a bag on the zoom attached by rubber bands to the lens, cover all of the zoom except the actual lens glass, this will prevent sand from entering the zoom body. The lens should be protected by a cheap filter that you can dispose of if damaged.

Do not change lenses. Take one lens and keep it on. Watch out for condensation forming inside the protective cover, remove the cover as soon as possible when it is safe to do so.

It isn't pretty, but a few simple steps using cheap plastic bags will make your dSLR almost water and sand proof. So much so that you could probably take it out in the rain.