From ‘ingratitude’ to uncertainty

In his last book on Central Australia, Wanderings in Wild Australia, W. Baldwin Spencer made the following observations about Central Australian Aborigines' apparent lack of gratitude:

Note an important assumption in this exonerating account: the flow of goods from whites to blacks can be likened to the flow of goods among Aboriginal people themselves. Goods which pass from one person to another, regardless of the culture of the person, are referred to as ‘gifts’. Assuming the sameness of transactions, Spencer suggested that whites who give are like fellow-tribesmen. It was not that Indigenous people were lacking in gratitude. Spencer's use of the term ‘gift’ allowed him a more positive view. If gifts from white to black and gifts from black to black are treated in similar (‘ungrateful’) fashion, can we not infer that Indigenous people see the giving white man as a kind of fellow tribesman? Indigenous recipients treat all donors in the same fashion.