Because to me it seems like a very pure way of separating a concept from implementation. In language and metaphors that are easy to understand and fun to read. I really like it. Now, in a very short time I can decide if Kafka can solve my problem or whether I should move on. I for one store information presented in this way much better, it's feasible that in 5 years I'm presented with a problem and the Otters pop into my mind.

Different people, different preferences I guess.