Safe doesn't mean sealed. It just means safe. Let's say you want to learn to fight. Wouldn't you rather do it by going to a professionally run 'safe' MMA gym where you can get guidance, learn from your mistakes and try different things safe in the knowledge that no one is going to cave your skull in just because you can't yet defend yourself. Surely that 'safe' environment is a much better environment to learn in than just going to 'unsafe' biker bars and picking fights with random people. I'd even wager that you'll learn more and faster in the safe environment than the unsafe environment.