Originally posted by Sitcom Analyzer
Fonzie was nothing but a cartoon character.
That was the whole point - he had this big mystery past where he used to be the leader of a gang and used to rumble alla time - i could theorize that he could've been made the leader (and not required to do much fighting) by virtue of his superior intellegence and street smarts - compared to what we've seen of the other Falcons, its not difficult to believe.
Throughout the series they made the point that Richie
never saw the Fonz hit anybody - he never needed too because he always averted any actual physical violence by intimidation or outsmarting anyone that wanted to fight him.
At the time the show aired, there was too much anti- tv violence sentiments going around for them to risk showing any, and possibly losing the strong family-oriented following they had.
Fonzie turned into a cartoon character, but he started out from a realistic premise - it just got warped by the whims of network, ratings, and advertisers. There wasnt any point in trying to defend the integrity of the character - no-one was complaining at the time.