Unless it is proven that driving on the beach is having a sustantial impact on the wildlife on said beaches either from pollution or the sheer weight of the vehicle. I say keep them open.

If it was my choice to go to the beach just for the scenery, ocean shores is the last place I would go. Not because of the cars on the beach, but the fact that it is an ugly beach. (dirty water, dead birds, flotsam and jetsam and that friggen wind) Drive north a few miles to kalaloch or south to long beach if you want a true beach experience... IMO far better beaches!