This explanation doesn't make any sense. It's not "certain people" deciding the election with a popular vote. It's all people. About 50% of Americans live in big cities and about 50% of Americans live in suburban/rural America. There's also the fact that the media exists to spread candidates messages and also the Internet, which covers just about every American.
I still don't have an explanation of how inflating anyone's voting power over other people's voting power is a fairer system then everyone's voting power being exactly the same.