Every business owner has the right to refuse service. In koh phangan we have many negative issues with young Israelis. They running around thinking they own the place. It’s good Pai is standing up to behavior they don’t want. If putting a sign up keeps rude and rowdy customers out, good. Many businesses owners want to have more mature customers. If some well behaved Israelis can’t go to enjoy certain places (like Bali) then talk to your fellow Israelis and get them to act more civilized.