And no one said they couldn't do it. However, it's still unreasonable.
And before you say that's ridiculous because these are private businesses, that's true, but they're befitting from government-imposed subsidies in the form of access to public rights-of-way and easements. Did you personally cut a deal to allow the phone and cable companies to cross your property with their lines? No? Then I dare you to go out there and dig them up. You'll find yourself charged with tampering with their equipment, even though it's on your property without your permission. And it's all because your local or state government has decided that these companies should, in the public interest, have the right to put their facilities on your property, and you have no say in the matter.
So, if you want a true free market where it's perfectly OK for any company to be able to extract anything from you as long as it's in a contract, then let's have a real free market and force these companies to have to negotiate to cross every single piece of private property. If you're going to argue that muni fiber is unnecessary because cable TV and Internet access aren't necessary services, then let's take that to its logical conclusion and deny them rights-of-way and easements. Then, once these are true private entities that receive no government subsidies, they can do any damn thing they want.