Michael is bolder than I in speculating on why the Dutch ride lousy bicycles. I generally take the Sybil Fawlty approach in explaining that sort of aberrant behavior—”they’re from Europe.”
But, contra Michael, I’d happily be the first to ride around Amsterdam on a fancy bike, parking it wherever I please. Because there are no bikes worth stealing, there are no professional bike thieves. Yet. A good lock will thwart crackheads and joyriding teens. It will do little to protect you from a skilled and determined pro.
As for the Dutch being as law abiding as Americans, perhaps they’re just as trusting as well. Which serves bike thieves well.