Right-- but often an NPC is merely scenery or traffic, in the sense that their behavior does not compete with your interests. What I found interesting about the football example is that the random strategy of the NPC-oach both suggested a deeper intelligence AND proved to be an apparently effective opponent.

Beyond reinforcing our tendency to project, as you say, a personal history on random behavior, it also highlights what a few other people have commented: that in many non-cooperative situations a committed random strategy is extremely effective, and perhaps more effective than a biased, seemingly "rational" strategy. (For another example, I believe Henrich's "The Secret Of Our Success" discusses the possible adaptive benefits of divination as a generator for random strategies among early societies.)