The frustrating part of this is that on a cost-per-square foot basis, bedrooms shouldn't be that much. They're basically twice the size of a roomette. Well, they're one foot longer. ... On the other hand, two roomettes should technically include meals for 4 instead of 2, so you'd think a bedroom would roughly cost twice what a roomette does.
It doesn't. At least in my experience, a bedroom is usually three times the cost of a roomette. As other posters have said, that's just supply and demand. ... It would be cheaper, we'd have views out both sides of the train, sit facing any direction we'd like, have two good berths with window views, etc. I'm not sure we'd ever really do that, but we'd pay for 2 roomettes before we paid for 1 bedroom.
And interestingly enough, the Amtrak Guest Rewards chart usually indicates a 50% premium for a bedroom. For example, a 2-zone roomette costs 20,000 points, but a 2-zone bedroom costs 30,000 points - not 60,000, as it would if it were "real money".