A local village has a really good café/ice cream shop used by lots of riders. The last time I visited it there was three £4000 bikes all secured to the railings outside by a single £5 three digit combo lock

, the wire of which could be cut with a sharp penknife! OK there was a guy, presumably one of the riders, sat looking at them all of the time from his seat in the café, but a lump of wood through the only door handle would have trapped him inside for the few seconds needed to cut the lock and be away with £12000 worth of bikes.
Of course carrying a decent lock would have made the £4000 bikes as heavy as a clunker, which would cost you less than a decent lock! As none of the bikes had as much as a tool roll under the back of the saddle i assume all three riders were true weight weenies unwilling to carry even an extra coat of varnish on their steeds

.