Look at it this way. Our society can operate at at a high scale of efficiency, where everything is used to maximum utility and absolutely nothing is wasted, or it can operate extremely inefficiently. It _only_ makes sense to consider the societal-wide efficiency--as you say, the problem and question are macro. So we can posit some ranking, some percentage of total efficiency.
However, 'Will it blend' is hardly large enough to make a huge dent overall in the larger percent. The resources lost from one netbook per time segment are not comparable to the resources lost in even a tenth of a percent decrease in efficiency, if you pardon the approximation.
Furthermore, 'maximum utility' is rather difficult to determine because 'utility' is variable. It turns out that apparently there's enough 'utility' in making "Will It Blend?" videos that we could even argue that this is positive efficiency!
Do you also get upset when cars and pianos are destroyed for movies and tv shows? Would you have us exert _more_ energy to generate the illusion in order to save good tools?