I dunno either. I think it's because Sleepy Dogs had a much better world compared to the Batman asylum. Or because in Sleepy Dogs enemies didn't fuckin slow mo fall to the ground while grabbing their heads with their god damn gigantic meat hands. And Batman was just fuckin flying all over the place in his combat, doing these gigantic leaps that were 1/4 cool and 3/4 distracting.
I'm going to put it down to the things outside the combat in Sleeping Dogs are far more interesting than Batman.
The combat in Streets of Rage 2 is more interesting than both batman and sleeping dogs.