> You can leave your bike unlocked because if anyone stole it the police would find them and return it since they can track the thief on a network of cameras.

In the US it is actually even worse than that.

The government and large corporations (basically the same people owning it all) will spy on you 24x7 for anything that they dislike you doing.

But if your bike (car, etc) is stolen right in front of many cameras providing video evidence, police will not do anything about it.

I know first hand people who have crystal clear video evidence of theft, gave it to the police, and they just don't care to do anything about it.