Symbolism in Chapter 15

I found chapter 15 exceedingly interesting, not because there was a lot of action or dialogue, but because the the symbolism which is evident in this chapter. I am sure that there is more allegory and whatnot in other chapters, but I found that which was in this one particularly intriguing. I feel like every single thing that occurs could be taken in a metaphorical sense, because so much of it seems unnecessary to the plot. from the knocking on the pipe in the beginning, to the smashing of the bank, and then the narrators inability to get rid of the bank, this chapter is rife with deeper meaning. I am not really sure what any of it means, and some it it may just be there to mess with readers, but I will give it a shot.
I think that the banging on the pipe probably has a lot of deep meaning, but what struck me about it was the disharmony of the community. The people are all getting mad at Mary for the lack of heat, and then at each other for the noise, but they only confound the problems by banging the pipe (other than the fact that their body temperatures probably go up some). What I found important is that there is a total lack of cooperation, or of the desire to understand anyone else. Everyone there just assumes the worst of the other people, and immediately starts banging the pipe to prove their point, or to ask for more heat, when it obviously won't help. Later though, after the narrator stops banging the pipe, the knocking goes beyond a protest for heat, and turns into a "ragged rumba rhythm". I am not sure what exactly that signifies, but it is undoubtedly important. Perhaps it means that disharmony can be harmonious, or harmony can be achieved through disharmony, or just the the narrator is causing the disharmony, or at least perceiving it. I welcome any other takes on this matter gladly.
The other symbol I found intriguing was the bank. A small, racially exaggerated, figure which contains many coins. The narrator uses it to bang on the pipe, but than it breaks apart and pieces and coins are strewn about his room. He has a need to hide all of it, but cannot find anywhere in the room to do so. This could represent the inability of anger to solve problems, or the narrators hatred for racism, or something altogether different. Probably all of these. My favorite part of the chapter was when the narrator was walking in the street, and repeatedly tried to get rid of the broken bank, and was repeatedly unsuccessful. The manner in which he was unsuccessful was for sure meaningful, but I am not sure exactly in what way. I think that the overall inability of the narrator to let go of the bank represents his inability to let go of his anger, and to let go of this thing which attaches him to his past. He also cannot get rid of the racial prejudices. I was really intrigued by this scene, and would love if anyone else could enlighten me with their takes on it.
One other thing that I would add is that at the end of the chapter, the narrator has a similar feeling as the end of the first chapter, when he is forgetting about the bad stuff he just did and looking blindly ahead to college, and the chapter where he ignores what the vet tells him and focuses on going to NY. At the end of chapter 15, he forgets about the broken bank and what it means, and focuses ahead on the night's rally.