I think that's a poor statement. Why did apple include display adapters in previous models, even for those people that don't use external monitors? Or why set 8gig standard on base models when some people may only use 4.Why should the people who have no need for such adapters subsidize the cost just so it can be included in your box?
You, and Apple are making the assumption that the majority don't use these things. Maybe over time, but like I said, phase them out gracefully without leaving a bitter taste with loyal customers.