The counterargument for this — although it is a counterargument in favor of other crimes — cannot be that in a more just society what he does wouldn't be a crime, because he knows that's not true, and is actually rather active preventing vigilantes in Gotham other than himself (or, of course, the people he trains and/or controls).
A possible counterargument, as much as I've grown to actively loathe Frank Miller, is that of course he's a criminal. He's a master criminal, an Arsene Lupin who has never had to steal anything, so he could indulge his ethics from day one. I'm fine with that Batman, but it's one that could/should embrace the fact that he's a criminal; do the same things he does, but with less of a chip on his shoulder (at least regarding, say, thieves; even career thieves have the right to feel righteous anger against a murderer, but Bruce breaking and entering into somebody's house to beat them up because they robbed somebody else's might be ethically arguable if you grant his skills as a detective and moral integrity, but he should at least be aware of the irony).
Not that Bruce will, ever. Because he's a generally mostly moral man, an assertion I'm more comfortable making about the animated series' Bruce Wayne than many versions in comics, by the way, but Batman is something he has to do, not something he chose to do. Batman is how he sort of copes with his trauma; morality and the law only factor into it because it was a criminal who killed his parents (for another scenario out of an infinite spectrum of possibilities, cf my Fuga fic). Bruce empathizes with victims, cares for people, wants to help even his enemies (again, more true for some versions than for others) but if that were his main drive he wouldn't be Batman, he'd be doing Wayne Foundation stuff all day long, and/or be a doctor, and/or enter politics. He's Batman because he was hurt, and the injustice of how that kid was hurt makes the concept of law a joke. He's not punishing criminals because they break the law. He's punishing them because they break people.