It is not uncommon. You're reading the news about police talking to dozens of witnesses in a crime. They heard the screams for help, they were watching the crime taking place, they heard and saw the victim/s pleading for help.... Yet, did not call the authorities to alert them. What do you think is the cause of the bystander effect?
I do not think witnesses are also to blame. Many people just do not want to get involved not understanding that they are sort of involved by watching a crime and saying nothing. More people need to understand that if you see something do not just look the other way, report it.
Yeah, people need to act. I understand the more people there the more everyone thinks, "Oh, it's okay, someone else will report this." But that is the wrong mindset. 40 people? Really? They could have intervened to stop this from even happening. Forget about dialing 911, 40 people can stop something. The same thing as these mass stabbings, the reason these knife wielding thugs and terrorists can stab so many people is that everyone is running and screaming. If five or six of these people stopped running and screaming and actually attacked the assailant they'd be able to stop him, disarm him, and hold him for the law.
You also have to remember that everyone these days are only thinking for themselves. You do not have those who are more of the hero type as when we were growing up. So you see all these people standing around watching and all they are thinking of is oh I got to get this on video and post it to facebook or I better watch so I can see what is happening and then be able to tell my friends about it later. You do not have a group of people but a mass of individuals who can not think like a group to help someone even if that is calling the law.
And that, sir, is a sin. We are all people trying to get along. Sure we're all individuals but we are all part of the human experience. We should all try and make it better for each other. I blame all of this on the policies we've been fed over the last few decades. Too much touchy feely, everyone is a winner, everyone is an individual garbage. Not enough, if you see someone in trouble help him out. Too much, hey let's take a video and get 100,00 hits so I can be famous. Not enough, hey, how can I help my fellow man today.