As it stands in the real world, there's lots of people of all ages who want to be super heroes. Not necessarily with powers. Just someone like Batman or Green Arrow or the like who is perfectly normal but fights crime. Even those who train to be able to fight almost never go the way of the movie Kick-Ass and actually try to pull it off. Those people we see in the news who have made costumes don't get into the physical stuff. They're helping people carry their groceries and whatnot. At most they might perform CPR sometime.
Now step into a different world. One like that depicted in comic books. One of the more recent Batman movies showed Batman-wannabes fighting Scarecrow and friends in a parking garage. Batman himself showed up and broke it up explaining that the difference between him and them was that he wasn't wearing hockey pads. Nor was he toting guns, but he didn't mention that. The fact that he'd inspired copy-cats is sort of the point of my thesis.
Batman has to remain a myth that only criminals know about because otherwise Gotham becomes filled with wanna-bes who Batman then has to smack around and send home. He's trying to protect people and barely trained and funded are just putting themselves in the middle of minor skirmishes and getting themselves hurt or killed. But in Boston, where Bats can't patrol, there's going to be nearly as many Bat-pretenders as there are cops. Sure, it's illegal to be a vigilante and the cops will be arresting them when they can, but it's still going to be happening a lot because Bruce Wayne proved it could be done.
This comic book universe has proved something else. Aliens do exist. Meta-humans do happen. How many kids do you know who have tried to use the Force after watching Star Wars? All of them, right? Often doing it well into their 50s and beyond. It's hard enough to keep kids from wrapping a towel around their neck and jumping off roofs now. How hard would it be when there are actually people who really can fly? Because how do you know if you don't try? Maybe you do have laser vision and you just need to figure out how to turn it on? We'd constantly be exposed to ads by con artists claiming that they can help you unlock your secret super powers. We might all be mutants who just haven't activated our powers. Around Chernobyl and Fukushima they'd need intense security to keep out all the people who just want to get exposed to a bit of radiation in hopes of unlocking some powers.
My point being that the comic book worlds are woefully under vigilanted. Superman HAS to stop all these accidents because otherwise a dozen other heroes are going to appear like lawyers on an ambulance.