Nerds who think they are soooooo special..typical narcissists...rules of common courtesy and privacy don’t apply to them.
People banning on cellphones at restaurants is also rude.
i carry personal recording devices for my own personal security. i am often alone and would rather not have liars railroad me or get into he-said she-said situations - much less an accident - and have people lie about what happened and have no proof they were lying.
What rules of privacy? It's a public venue, and, wait for it. You have no expectation of privacy in a public venue. Is the owner going to ban customers with smart phone cameras too? I hope so, because his business will go into the toilet.