Firstly: their property is on our (the public's) right of way.
Secondly: Clearly I should apply your reasoning to other utility companies.
Lets assume you're a libertarian, and out of touch with reality.
As a result, your utility company, which is run by a greedy bastard, has decided to cut you off from water and electricity because:
a) He doesn't like you
b) You didn't buy his brother's product when it was offered to you
In any case, according to your argument, that is perfectly fine.
Wait, it gets better!
Lets assume you have a river running through your property...
Is it ok to drop some poison into the stream? It is on your property at the time, right?
Mapping back to today:
The bits flowing over Verizon's wires are NOT (for the mostpart) Verizon's. Why do they get to touch them?