Okay, so I'm gonna go ahead and be that guy: where was he during the Metropolis battle, then? He couldn't hop in a Bat-Plane and help out? And when Clark showed up at the military base, are we really supposed to believe no one mentioned that other cape-and-costume-wearing guy, or did those mentions just oh-so-conveniently happen off-screen?
Well I'm sure in this
world Batman is still nothing more than an urban myth that no one really takes seriously. He probably hasn't revealed himself in a big, dramatic way yet, like we saw at the end TDKR.
Plus, there's the lack of superpowers thing.