In the grand scheme of things, I've found the feud between Rhodes & Sandow to be pretty interesting and well done overall. As another poster already mentioned, one explanation why some of the crowds have been more receptive than the others is the fact that neither of these men has a ton of momentum going for them right now. After all, they've spent most of the past several months being jobbed out in either tag team matches or in one singles match after another to bigger stars like Orton or Sheamus.
In the grand scheme of things, Rhodes' being angry with Sandow for how he won MITB might not come off as the most exciting or original idea. As for it not making any sense, well if you're someone that completely ignores the fact that human beings are highly emotional creatures that often react based on emotional reactions, then it really doesn't make sense. However, friend or no friend, it's perfectly natural to have feelings of bitterness when something doesn't go your way due to the actions of a friend. Ever been cockblocked by a friend who maybe swooped in while you were in the midst of putting the moves on some gal? Generally speaking, it's the same thing here. Cody Rhodes was about to score, the gal in this case being the MITB briefcase, only for Sandow to swoop in to not only block him, but to make off with the gal himself. In real life, would some friends simply brush it off and let bygones be bygones? Absolutely. In real life, would some friendships come to a crashing halt over bruised egos & feelings of bitterness? Most definitely. Cody Rhodes doesn't exactly come off looking like a saint by merely being the bigger man and letting things be, but whoever said he was supposed to be a saint? It hurts when a friend screws you over, no matter what the circumstances are and some people react to different situations in different ways. The entire plots of movies and television shows have revolved around situations in which friends put the screws to one another for some sort of personal gain. Why's it okay in that media forum but it's not okay for pro wrestling?
This sort of scenario has been used in pro wrestling since time immemorial to break up tag teams and friendships for the purpose of turning one of the characters to engage in a feud with the other. Promotion after promotion has used some sort of variation of MITB in which the winner of a match gets a title shot or something along those lines since before Vince McMahon was old enough to shave. The reason why it keeps getting used every so often after all this time is because it works.