For the cinema (unlike the comics, where he'd been a member of the Justice League for years and whatnot by the time they tried to play the "urban legend" card), I can buy a version of Batman who keeps a relatively low profile and whom most people in Gotham have never seen. Even if things like the Bat-Signal exist, skeptics might speculate that it's all a stunt by the Gotham PD to keep the criminals in line.
The car is harder to rationalize, but anyone could be driving the thing, it doesn't mean there's really a guy in a bat costume who runs around doing all those things that they say he does....
Legally, he might be completely "off the books", with the courts not recognizing his existence.
The car is harder to rationalize, but anyone could be driving the thing, it doesn't mean there's really a guy in a bat costume who runs around doing all those things that they say he does....
Legally, he might be completely "off the books", with the courts not recognizing his existence.