This incident demonstrates humor about something serious. It also causes Huck to confront his feelings about society again. Huck has been having an ongoing battle with himself about good and evil. He has decided that slavery is wrong, whether society thinks so or not. The shooting and theft also give him an opportunity to realize that things and people are not what they seem.
My guess is, you want to hear more about our thoughts in regards to Huck's feelings about the climax of the feud. In reality, it's yet another way that Huck shows himself to be intelligent, ... in not understanding the point of the feud and eventually escaping (happily) from it!
The fact that Huck is a witness to the violent shooting (and MURDER) of Buck, which is the true climax of the feud, is the catalyst behind the reasoning to return to the mighty Mississippi. This violence in the midst of "Southern gentility and chivalry" is appalling. Whether Huck and Jim realize it or not, they are escaping truly uncivilized behavior and returning back to both nature, friendship, and peace.
I'm not sure what you mean by "discuss." The first post has done a great job of describing what happened, but I'm not sure what you want discussed. Perhaps you can respond and give us some guidance.
My main reaction to the climax of the feud is to say that it shows how foolish human pride is. We see the two families fighting over something that no one even remembers. Because of this forgotten insult (or whatever it was), Huck's friend Buck dies at a horribly young age. It is all so pointless and terrible. I think that Twain is trying to use this episode to criticize human beings' tendency towards pride and (in particular) towards violent manifestations of pride.
The family feud between the Grangerfords and the Shephersons stretched back "thirty year ago, or som'ers along there," according to the history provided by Buck Grangerford to Huck, aka George Jackson. Huck's first exposure to the existence of the feud occurs when he and Buck encounter Harney Shepherdson in the woods.
As a favor to Buck's sister Sophia, Huck retrieves her forgotten Testament from church the next Sunday afternoon and discovers a note with a time recorded on it hidden between the pages of the book. Miss Sophia is thrilled to receive the note, but takes care to make sure that "George" wasn't able to read it.
The next morning, "George" arises to find all the Grangerfords missing. He eventually learns that Sophia was missing and apparently had run away with Harney Shepherdson to get married, so all the family was involved in the chase to stop them before they crossed the river. Huck heads down the river road and comes to the area where the two sides are shooting it out. During a lull in the fighting, Huck is able to talk with Buck and learns that several Grangerfords and as many of the Shepherdsons had been killed and that Sophia and Harney had made it safely across the river. Buck is angry with himself for not killing Harney during the encounter in the woods. Huck witnesses the shooting and killing of Buck and another cousin before he and Jim relaunch the raft to continue their trip down the Mississippi.