One of the problems is with bike shops is they usually have all the expensive stuff on display, just secured with a flimsy wire through the wheels, easilly cut releasing all the bikes, poor recording cctv, if any fitted,older buildings with access from the roof or rear doors, in properley secured, or ones that open inwards.
So bike shop owners, cctv, with secure dvd storage, decent alarm connected to monitoring station,
Steel plate on rear doors, with metal gate on the inside, hinges bolted through the brickwork,with decent locks, dont lock during opening times if a fire exit,
perforated roller shutters on all g/f windows and leave a light on at night so people can see in.
Razor wire could be installed in roof void, but then in a fire some fire man is going to seriously hurt himself,