I don't know of any instances this is happening, I'm asking this ahead of time. My friend uses 100+ GB per month. Yeah I know I was shocked too. Usually Pandora and the big one, Netflix.
I know they CAN do this, as I stated. However, if there are bunch people off contract, using a ghost line or paying full price to get new phones, and the top data users started being kicked off, wouldn't that be a dumb idea? I mean, no contract is a bargaining tool for us customers.
I told my friend this: If she gets a ghost line, uses that for a new phone, and pays the $13 per month or so with taxes and fees, and they take her unlimited, she can walk away, not buy any data, and just keep the phone she's not using, stiffing them probably 80% of what she had been paying.
If a lot of people started leaving because they thought their unlimited would be cut off, even a rich company like Verizon should feel it in the pocket book. Word would spread very quickly. I haven't heard anything on here, and this is where we would all hear it, if that were to happen.