Sorry, Shoo. I don't agree. A person doesn't choose to snore. It's not A's fault that he has this problem, and it's embarrassing (not to mention unfair) to be punished for something that can't be controlled. So, a person should be out the money to cover the full cost of a room because their roommate didn't want to compromise? What if they're financially strapped, and had to save for the trip and budget carefully? If that proved to be the case, their trip is now ruined because B has to have his way.
Maybe I worded that badly, but that's what it sounds like to me, and I'm siding with A on this one. B chose to move to another room, and if I'm reading right, he chose not to use earplugs or try any other solutions. It sounds like he put the onus completely on A to fix the situation, and I don't think that's right.
Let me just reiterate that I've spent sleepless nights because the person I was rooming with was a snorer/teeth grinder/sleep-talker. So, I'm not completely unsympathetic. I just think that B handled it very badly.