Those were buffet cars... Totally different then what I described but I'm fairly certain you would hate them too just because it is different.
I knew what you were talking about and even though I really dislike buffets like Dave (hate would be more accurate) I've had no particular problem with Panera Bread or Pei Wei or other restaurants of similar design. There's no ambiance to speak of, and it's definitely loud and downmarket compared to a more traditional table service restaurant, but it seems like it might be workable. I think such a project could be successful if handled with care and precision.
On the other hand it's understandable for folks to be hesitant to go along if they think it sounds like a buffet. Friends, family, and coworkers have convinced me to try buffets with every cuisine and price point imaginable. All over the country and all over the world from $5 to $100 per person. The only thing that tied them all together was the universally lackluster experience when it came to quality and freshness. I remain convinced that there is simply no such thing as a good buffet.
Even if you spend $100 on a buffet you're not getting anything truly special. Best case scenario you're really just buying a $25 entree with extra servings for free. If you're lucky those extra servings are also worth around $25 and after stuffing yourself silly with four plates of moderate quality food you've managed to break even. How is that a good value? Fargo is one of my favorite movies and even though the blood and violence never bothers me the short but realistic buffet scene makes my stomach churn like it's sick.