Reliable stats are hard to come by, but Delhi, Johannesburg, JFK all have bad reputations. For a long time Kuala Lumpur had a gang working with the X-ray guys to tag juicy targets, but they were busted a while back.
Problem is, cling wrap won't stop a determined thief, it'll just make the theft evident -- unless they just grab your whole bag instead.
Is there an insurance company that will pay out if the seal is broken? Probably not, since then the customers would break them themselves to claim theft.
