There is no "real" deterrent for shoplifting, only embarrassment (if you are not a professional shoplifter).
Professional shoplifters have no embarrassment, therefore have no deterrent.
I read somewhere that only an extremely small amount of stuff gets nicked via shoplifters,
whereas most of the goods get stolen by staff / delivery / storage and other handlers, even before it gets to the shops. [Obviously I could be wrong].
I think the word shoplifter does not seem to have the same stigma as thief
