I am sorry, but your logic is flawed.
Boot Camp is for humans a rather recent invention. Boot Camps became necessary the moment the civilisation had attained such moral value that they became necessary. That is however not their origin. The 20th Century boot camp (as seen in Bad Lads Army, Full Metal Jacket) etc etc is derived from the warfare in the Napoleonic Era where discipline was everything. You had to be able to stand and be shot at, then be fit to return the favour. The general style has not changed all that much between 1750 & 1950. The same focus on Discipline so you would remember your basic skills when the bullets started firing. Today, their purpose is as you state, but not to convert, merely to bring forth the qualities our ancestors have had since the Stone Age.
Wherever there have been humans, there have been conflict. Wars have shaped our entire history and I would daresay War Alone. I do not say it is our genes, but it is a part of our nature - to fight or flight. If it was not in our nature, it would be much more difficult to incite populaces to war.