A situation like that is exactly where the term bystander effect came from.
They probably all thought since it happened in public that someone else would do something about it.
A little over two years ago I was doing laps at my pool while two groups of people sat on either side and glared at each other while blaring their respective choices of music on their respective choices of boomboxes.
Unbeknownst to anyone except for me once I realized, one of the kids was drowning. I have no fucking idea why he jumped in, but he almost landed on me when he did. I didn't really think about it until hours after the incident but that was the kid that ended up nearly drowning.
I finished my lap once I suspected something might be wrong and asked everyone at the pool in a loud voice if they knew that kid right there, and whether or not he could swim. It was only then that one of the girls got up and said "oh my god save him save him! He can't swim!"
I was the only person at the pool NOT screeching like an absolute monkey. It was like a bunch of our ancestors at a goddamn waterhole watching one of their own being eaten by an alligator. Everyone was screaming. But nobody was doing anything.
I then realized that if I did not save this person, he would die. In a sample size of what had to have been close to thirty people, none of them had the presence of mind to do a single thing except scream. It was like they all believed they were the ones drowning, and not this other person. I grabbed the lifesaver first because I've seen those videos where someone comes to and holds on to their would-be-rescuer, drowning them both and I was damned if I would let myself die for this dumb kid.
When I got him out nobody had yet called 911. None of them knew how to do CPR. I cursed at them and told them to call, and took turns doing compressions with a young man until the paramedics got there. I was convinced the kid was dead when I left. Later I called Tampa general and found out that he was actually okay in the end which truly shocked me because what I saw and heard made me believe with certainty that I had been witnessing a death rattle.
The thing I learned is something I should have been smart enough to know prior. Maybe I did, and the event just made me more cynical about it: people are stupid. They are fucking stupid, and the stupid people are everywhere. There's billions of them. They don't know how to do anything except eat, spend money and play on their goddamn phones. They are only alive because humanity has advanced to a point where its technology accommodates the infinite retardation of the bottom of the barrel. Otherwise they'd be eaten. The lions of the world would be fucking fat from all the surplus of dumb people. If it had been me drowning, I'd have been fucking dead. I would have literally drowned in front of thirty people who sat there and did nothing.
Hell they wouldn't have even fucking noticed.
Funniest thing about the whole situation is that afterwards the family of the kid gave me shit because blood was coming out of his mouth.
You're welcome, you vile turds
EDIT: "Kid" means 200+ lb teenager who should have been taught how to swim, especially if he was going to be at the goddamn pool
