If you lock or wrap your luggage, I think it just makes the thieves pay attention to it.

I had cameras pilfered out of checked bags at both JNB and CPT. SAA managers made me get a police report -- helpfully, there's that police office there in the terminal who seems to write a lot of these particular reports. Then SAA treated me like a fool for trusting my property to them.

If pilferage doesn't even embarrass an airline or an airport, you shouldn't ever check anything you care about.