I understand it's annoying to jump through hoops to prove your intelligence, but what else are we supposed to do? There are already colleges like Western Governors University that provide fully accredited, self-paced, online college degrees. Are you wanting the top colleges to do this too?
You've got to question the impact on the college's social status that such a change would bring. People don't (generally) go to Harvard for the superior education, they go for the social status that being a Harvard graduate brings. If we make such a school globally accessible, wouldn't that dilute that status?