Apart from the sale of relics to battlefield visitors, a practise that is probably now minimal, there is little of commercial value to those who desecrate monuments and cemeteries in Natal. There is not and never has been any treasure to find, there are only small amounts of scrap metal to recycle , and easier and more certain ways (e.g. murder) to collect human remains for muti (medicine). The muti motive seems to be the one most often suggested for this practise and, if true, it will not end. As long as supposedly intelligent Chinese prefer to rely on powdered rhino horn rather than far cheaper and more readily available Viagra, so Zulus, who lack many of the advantages of Chinese, will continue to use traditional medicines.
Something that is seldom mentioned, especially in polite society, is that the vandalism may have no purpose other than to annoy the people who erected the monuments. To most of the residents of Natal, Slavery, Colonialism and Apartheid are one and the same and manifestations of these 'crimes' are to be disrespected. (Except, of course, for obviously desirable outcomes such as cell phones, BMW's and Kentucky Fried Chicken).
It is worth remembering that the perpetrators of this sort of vandalism are seldom, if ever, identified, arrested, charged, convicted and punished.
Eventually, the people prepared to pay for, a restore damaged historial monuments in Natal will give up and the problem of their existence will end.