There's a big difference between simulating a zombie 'crowd' and actual ambling semi-believable groups of people. Surprisingly, especially before everyone just stood around staring at their smartphones, people tend to behave much differently than deranged, mindless zombie hordes and have a far greater range of expression and things that they can do.

@korwin: Nah, that was Sony striking back at MS for taking the 180 p's. "They took away our p's, mess up the PC version (aka, just do a Ubisoft PC port)."