>>113449900>>113449909>>113450519Frank Castle has a higher body count.
The audience knows Frank’s history, but to Batman he’s a guy running around shooting mobsters, no different than the vigilante murderers he’s dealt with before, who have a tendency to get innocent people killed or start going after the poor and downtrodden too.
Batman holds out hope for rehabilitation for many of his villains. As far as he’s concerned, Frank belongs in Arkham too.
Frank is operating in Gotham. Batman is canonically territorial about Gotham, but would likely leave Castle alone in New York like he currently does Harley Quinn since New York is Wonder Woman’s town and thus her business to deal with or not.