The new rules sound as if they were devised by central government to raise revenue, to help with the economic crisis, but I would doubt if local government will agree totally with the measures as it could make their local businesses less profitable, or uneconomic, resulting in closures, loss of revenue for the local municipality, and only make the economic woes worse for their local tourist trade.
I would hazard a guess that these 'rules' will be largely ignored, as are the No Smoking regulations, motorcycle crash helmet laws etc., and common sense will dictate what is done and what is ignored.
At least that is what I would hope happens, as many places we visit in Greece are so much better for having tables and chairs on the beach, some shade and so forth, what would Shirley Valentine have done for her dream of a glass of wine on a beach?