[reading-at-work]

WorldMaker's answer to this comment is great. I would TL;DR it by saying that while there are always multiple phone companies to choose from, there is usually only one cable or fiber internet company, which is what matters.

In every state I've ever lived, for example, Comcast is the only company that provides acceptable internet speeds. DSL and satellite providers don't even come close enough to count as competition. So Comcast has the localized monopoly on the infrastructure necessary to actually provide a good product.