A legitimate question.....
M.Frog is correct....driving on beach is not permitted. However, people still do it at times.
Now, since there are beaches left in the world where driving is permissable on some beaches (U.S. , Australia, and New Zealand being 3 of them) I am trying to figure out why there seems to be so much "angst" over what I often see to be "innocent" questions. For example, hunting is "not allowed" in the DR. If someone comes into the DR1 that is a hunter and asks if hunting is allowed, why can't the answer just be given that "no, its not permitted" (even though dove, boar, and other bird hunting goes on all the time here in the DR in certain areas).
The law in the DR is kind of like this....1). What the law actually is, 2). How the law is interpreted by local citizens 3). How the law is interpreted by expats 4). How the law is interpreted by local & national government officials (certainly can be many interpretations here) 5). How the law is interpreted by the legal system (certainly can be many interpretations here too) and then 6). How you figure out who you will need to pay when you go ahead and do what you want to do anyway (irrespective of the law), get caught, and then find out you are in trouble.
Suerte!