Again, a very selective reading of 'surviving hunter-gatherers': you've taken the Dobe to be representative of all pre-agricultural people still existing, and extrapolated back to assume that this was the norm throughout all societies in the distant past.
no not just the Dobe. again from the Jarred Diamond article you apparently still refuse to read:
Are twentieth century hunter-gatherers really worse off than farmers? Scattered throughout the world, several dozen groups of so-called primitive people, like the Kalahari bushmen, continue to support themselves that way. It turns out that these people have plenty of leisure time, sleep a good deal, and work less hard than their farming neighbors. For instance, the average time devoted each week to obtaining food is only 12 to 19 hours for one group of Bushmen, 14 hours or less for the Hadza nomads of Tanzania.
Have you heard of these guys? http://en.wikipedia.org/wiki/Yanomami
and in particular: http://en.wikipedia.org/wiki/Yanomami#Violence
these are not band level, nomadic gatherers and hunters.
these are tribe level horticulturalists who live in villages, with hierarchies and division of labor.
and as such, they do not exemplify the primary lifestyle of our ancestors.
it is not my personal belief, because i smoke too much weed and am prone to idealism, but commonly accepted in the field of Anthropology, that the band level gatherer/hunter is the primary form of social organization practiced by human beings for most of history. a lifestyle characterized by egalitarianism, equality, etc.
Suppose that an archaeologist who had visited from outer space were trying to explain human history to his fellow spacelings. He might illustrate the results of his digs by a 24-hour clock on which one hour represents 100,000 years of real past time. If the history of the human race began at midnight, then we would now be almost at the end of our first day. We lived as hunter-gatherers for nearly the whole of that day, from midnight through dawn, noon, and sunset. Finally, at 11:54 p. m. we adopted agriculture.