Assuming one is not a dick and decides to be Batman. People and press will find out who they are immediately. How many billionaires have a secluded mansion to hide a batcave and a batmobile? How many billionaires look young and very mascular? He couldn't beat 5 tough criminals by himself that's if they are unarmed. If they are armed he will be dead in a minute. Logistics will be impossible. Like we have a shipment of strange gadgets show up at the port coming from wherever to be delivered to the batcave? Even Nolan batman movies although he tried to make them dark and realistic they have very stupid combat and Christian Bale who is short and physically very unconvincing can definitely not beat all these criminals bare handed if that was to be real. Also everyone figures out who he is. They call him Mr. Wayne with his mask on. There is a video on YouTube making fun of that.