However, this works opposite by not hiding in the mass. The thief hides in the mass, as bikes themselves don't flee the scene when a thief is in sight. So the trick is to find a good place for my bike. As I have a fragile racing bike (old and cheap but technically in good condition), those massive outdoors parking systems are not good places. People pull and push to get their bikes out, and a racing bike wouldn't survive that for long. So I find places where my bike is safe.

It's always fun to see that I park my bike in an empty spot, and after an hour or so the space if filled with other bikes.

Now that I ride a much more expensive cargo bike, I don't worry about it anymore, and it hasn't been stolen yet. Are cargo bikes less attractive? Hard to believe, but it seems to work.

In most places in Netherland, parking wherever you like is no big deal, but there are places (train stations in particular) where bikes really need to be restricted, or there'd be no room for anything other than bikes.

It's the same as with cars: the occasional randomly parked car is not a big problem, but once you've got thousands of cars being parked all over the place, it becomes time to restrict them to designated parking spots. It's no different with bikes, except you need a lot more bikes to get to the point where they become a problem. Dutch cities have that many bikes.