If I were afraid of it being stolen/damaged, I wouldn't ride/leave it there. My bike is for transportation... so I'll lean it up against a rack, concrete post, whatever I'm locking it to. If it gets beat up, great, it's less likely to be stolen. If I can afford a $3K bike to ride every day it'll get the same treatment... although it is unlikely I'll ever drop $3K on a bike for myself. My bike was $400, and I probably have another $400 of parts I've put on (fenders, pedals, seat, frame pump, lights, etc etc etc). It has acquired scratches from stuff I've locked it to, from falling over, and general manhandling.