Stevan, I think you would be lucky to get mugged by an Air Hosty,
Kindly define your sensible pre-cautions?
The SA Police service lists about 27 sensible pre-cautions all of which need to become routine and automatic.
of those only about 6 involve not getting mugged.
the rest are to do with in your home and in your car safety.
and you and your wife and your kids have to do them every time.
because the criminals who specialise in Armed home Invasions and/or Hi-jackings only have to get it right once.
THATS whats different about SA Crime.
Now agreed, Cape Town and Port Elizabeth and Durban have less incidents of Violent Crime IN YOUR HOME, but they do occur there.

As to your question about thousand and millions of tourists not being attacked , Home Invasion Gangs look for one bit of loot more than any other, firearms, none of which Millions of Tourists to SA are allowed to bring in, yet Tourists do get raided in B&B's , some were reported last week in the press.
Now ask your spouse or any wife in SA what do they fear the most? a mugging or 4 plus armed young guys holding you hostage in your own home without anyone knowing about it?

which does happen often in SA, and I dont care that it might also happen in Chicago or Illinois or Panama, you are going to SA .
However,if you really want to do a comparison with Spain, kindly compare Rapes,Murders and aggravated Robberies, thats what makes SA people live in fear.