To try an answer the question of what the customer wants is outside the scope of our side of this business. Our responsibility is to fly the airplanes safely and smoothly for a fee. It really doesn't matter if they are RJs or A380s what does matter is how much we get paid to do it.
Now what does the customer really want?
The best service for the cheapest cost. It is that simple.
It is marketing's job to figure out the best mix of service for the price not mine.
The whole reason for RJs is not to cut costs it is to provide the right number of seats in the market at a cost which will support and make a profit. UAL could put a 380 on the ORD to OMA route and probably even find a price which would fill every seat, but make a profit? Not my job to figure that out.
Personally my opinion is; I will provide the customers under my command safety, smoothness and professional conduct the rest is up to marketing.
Also if the customers would pay for First Class seating and service on all those RJ routes UAL would offer them in a heart beat.