Because the internet isn't just entertainment, it is a telecom service that provides common carrier services. The internet is also how many Americans make phone calls, access government services, organize physical travel, and conduct their banking. When I pay for internet access, I expect to be able to access any site on the internet. I don't want Comcast saying, well you can't register with the DMV because their ISP isn't paying us extra--that's why net neutrality is important and is fundamentally different than the inapt comparisons you've provided.

Further, the telecoms embrace their common carrier status when it does things like allow them to use the eminent domain powers of the government to construct infrastructure across private land or on public lands--which is fantastic as long as they reciprocate by providing common access to their infrastructure. Amazon didn't need use eminent domain powers to build their warehouses on a promise of a universal public service.