Of course, I am not advocating for the theft of bicycles. Quite the contrary. Bike theft is a problem in Sacramento. Homeless guys are thought to be common culprits in this activity -- and I believe that there are more than a few homeless guys who do steal bikes (with "common culprits" being an overstatement).
Homeless guys, too, have their bikes snatched on many occasions. As the video shows, a bicycle can be stolen while the public watches. There are several reasons for this: In a crowd, if something that might be illegal occurs, each person will tend to believe that someone else will take on the responsibility (and the burden) of reporting the apparent crime. Too, it is easy to presume [that is, to adopt a self-serving rationalization] that someone trying to bust the lock on a bike (or jimmy the window on a car) is the owner of the bike (or car) and that the likelihood that a crime is occurring is small.
I think the moral lesson here is that we should all look out for each other and if we have a camera of some kind, take a picture or make a film of what's going down. And if no one else is evidently calling the coppers, we should -- even if our call seems pretty likely to end up being a waste of people's time rather than a day saver for some bike (or car) owner who is in the process of being victimized.