I tend to agree but online courses allows school to admit more people. Therefore the value of that limited resource should go down, along with the price. Although Harvard hasn't announced an increase in first year admittance, I suspect if this is succesful they will start to increase enrollment and therefore should bring the cost down.
Not without increasing capacity of professors, TAs, and administrators, and then the facilities to support all that new staff. Campus facilities for students is only one part of the cost structure.
Stanford's all-online CS106A ("Code in Place") in the Spring quarter was organized in about two weeks and fairly successfully scaled all aspects of instruction to ~1000 online learners.
Curious how they scaled. Just threw money/TAs at it? The limiting factor in my department with expanded online offerings is the number of people willing and able to sacrifice currently strictly limited on campus research hours to TA. There are a finite number of students that a given TA can handle, and it quickly can be an overwhelming amount of work responding to emails and grading.