[Roxolan]

>it never stops to notice that the Joker is actually the hero. [...] his various games only have one innocent casualty

Blowing up a major hospital (even an evacuated one - at very short notice I might add) or having firefights in the streets does cause casualties, even if none are shown on-screen.

For that matter, the joker WANTED more casualties, as outright stated in the ferries incident. A failed mass murderer is not a better role model than a successful one.