Years ago, the Carolinian did have that, and it was wonderful. The cafe car was next to the BC car, and the attendant would come through with a cold drinks cart but would also get you coffee if you wanted.
I haven’t been on the Carolinian for a while, but I’m sure that service is long gone.
By the way, it isn’t the distance that’s a problem for me—I routinely walk about 8,000 steps a day on ground that isn’t moving—it’s the wobbliness and trying to carry hot coffee and keep my balance, especially where there’s no seat back to hold on to easily (like that open space where the luggage goes).
I also don’t want to sound like a spoiled prima donna—I don’t mind a walk through two cars—I am simply just terrified of stumbling and spilling coffee on someone. I’ve stopped bothering with the free coffee for now—it’s not worth the stress.