Both the camps and the "scorched" earth policy were actually started by Lord Robert's in 1900 and not Kitchener, who was originally merely Roberts Chief of Staff until he returned home, moreover, to the best of my knowledge, the concentration of civilians into camps actually began on Cuba in 1896.
Once the enemies capitals had been taken and the guerrilla war phase began the War Office had absolutely no answer whatsoever, it was a new war for a new century.
Their response was to build block house lines to guard the all important railways which supplied the army, but, this did nothing to stop the enemies sabotage, so the next step was simply to remove their source of food and supply, take those thirty thousand or so farms out by burning them, place their inhabitants into the care of the District Commissioners.
The fact that the Boers own families had assisted them meant that they had exposed themselves in a way which would not just be overlooked by the War Office, the war was clearly not going to come to an end and that must have seemed really obvious at the time.
The problem was that those District Commissioners had no experience at doing this task that they had been given, they had no idea about how to organise a camp, critically, the water supply, sanitation and so on, at the end of the day, you are dealing with a large number of people, all in a very small space.
Importantly, it has to be remembered that these Boers, had, in effect, been living in isolation for one hundred years or so, the War Office could not be trusted to look after their own men, let alone the enemies families, as soon as you exposed them, unintentionally, to disease, the blue touch paper was well and truly lit and it proved to be very tragic indeed.
I certainly would not try to justify the policies either way because I was not around one hundred and sixteen years ago, but, I have to say that I find it all very unpalatable, I doubt if the gold under the Rand was really worth all the suffering, but the three particular men that I'd like to discuss this with, Cecil Rhodes, Alfred Milner and Joseph Chamberlain are all long gone.