First, choose your own fights and choose them carefully. Part of the problem with bars is that they are places where other people can--and do--make the decision or have input into it. If you're interested in pursuing a random walk principle with respect to fights, bars are among the best places to do it. Reread the message with which you began this thread and you might see what I mean.
Second, don't get into fights unless you know for sure you can win them. Winning for old people and smart people does not mean defeating your opponent. It means emerging from the fight with your initial number of body parts, no holes that leak precious bodily fluids, nothing broken or bruised, no more opponents at the end than at the beginning, and no law enforcement officer standing on your back, hitting you over the head, or pointing anything with a hole at you. And it also means that your opponent is not maimed or dead.