GANGNES: The text beginning with "I know it is..." and ending with "But I wander from my subject" several paragraphs later was cut from the 1898 volume. See text comparison page.
STOVER argues, "The reason Wells cut this passage from the book version is probably aesthetic. He did not wish to give away too much, if he were to keep with the novel's deepest artistic ambiguity" (188). However, this assessment risks oversimplifying an extensive edit. Apart from "giving away too much"--offering a lot of information that the narrator would not find out until much later and therefore informing the reader of details about the Martians relatively early--this passage can come off as "preachy" or overly philosophical in a way that Wells may have later decided he disliked.
This omitted section tells us a great deal not only about the Martians' grisly study of a live human subject, but also about the narrator's ideologies. Looking back on his first glimpses of the Martians from a later time of safety, the narrator offers a kind of persuasive philosophical essay (he is, by trade, a professional writer of similar essays) on the ethical and moral lessons to be gleaned, from the Martians' behavior, about humans' treatment of other animals.
While the passage may "wander from [the narrator's] subject," it offers an intriguing dissonance between the narrator's terror of being killed by the Martians--to the point where he sacrifices others' lives--and his cool, high-minded defense of their consumption of human beings.
In the end, Wells retains only the first sentence of this passage in the volume to speak very briefly to the narrator's philosophical thoughts on the matter. What we gain in narrative flow and "artistic ambiguity" we may lose in characterization.