A.V.I.A.F.
Captain
I think that Bones was intended to be the character with whom most people (in the 20th century) could relate. His overall attitude was anachronistic (constantly complaining about the concept of beaming, making racial remarks about a non-human during a time when racism was not only in poor taste but was seen as archaic, blasting the idea of risking lives for the mission--even though that is a big part of the mission) except when it came to the practice of medicine.
So, I think that his constant grumbling was a way for his character to be an anchoring point for the viewers to have a sense that there was someone on the ship who may have felt and reacted the way that they might have. I think it helped to link the audience to the strange futuristic universe of the show which has now become all to familiar to us. I think we need to think back to what it was like before ST came to television so that we can understand this.
So, I think that his constant grumbling was a way for his character to be an anchoring point for the viewers to have a sense that there was someone on the ship who may have felt and reacted the way that they might have. I think it helped to link the audience to the strange futuristic universe of the show which has now become all to familiar to us. I think we need to think back to what it was like before ST came to television so that we can understand this.