Well, the part about martial arts that some people don't pick up is about self control. Having the ability to beat someone to a lifeless pulp easily isn't something to take lightly. Once the highschool phase ends, it's a lot easier, the whole "herd" mentality of life is over. You can do good stuff and bad stuff and not have to deal with the normal gossip reputation bullshit. Knowing you can beat someone up means you need to be the bigger man and walk away, defuse the situation, or even run away. Usually it's over petty shit, but if someone is threatening your family or something, there are cases when you might need to hurt them. But at the end of the day, if they're a trained marital artist too, your best bet is to walk away. It's not just fighting, there's dirty fighting too you have to worry about. Eye gouges, nuts shots, throat strikes, headbutts, weapons, etc. It's not worth gambling your life on the outcome of beating someone up over petty stuff. You also can end up serving serious time, and while everyone knows the best feeling is to make them feel like shit, bleeding on the floor, begging for mercy, it really isn't worth the risk, there's too many factors you can't account for. There's no way to be 100% safe. If you want to feel like a bad ass, go fight professionally.
Story time.
There was a pretty well reported story that happened over the last year, about two highly trained professional MMA fighters, one that fought in the UFC and Bellator and fought for the Bellator MW title. So basically, they were in a gas station, and being the cocky douchebag that many MMA fighters are perceived as, he makes an advance of some sort toward a woman. She rejects him, and then the guys assaults her throwing some drink on her. She leaves and tells her friends outsides. A gang of guys came, 4-5 of them, and they start fighting. It eventually ends up outside the station. Note, this is in Brazil, where martial arts is a big deal, you don't know who trains or not. So anyways, they start fighting a group of guys, him and his friend. A guy runs up behind them with a 2x4 knocks said fighter out. His friend is with him, he gets knocked out too with the 2x4. Some other douchebag, soccer kicks him to the head, and pounds his face in. The other guy, who had nothing really to do with it, ended up in the hospital and probably still is at this time, unable to do normal life stuff. He had to have multiple head surgeries, physical therapy, etc. Remember, these are two trained martial artists, and professional fighters. One of them nearly ended up dead, just being in the wrong place at the wrong time, with the wrong people.
Did the work, and found the video
https://www.youtube.com/watch?v=UzOhwRPApcs
What's the moral of the story? I shouldn't have to tell you by now.