The fact that you use the word greed shows that you're not likely to ever understand, but let me try. VZ's "job" isn't to give you phone service at a rate that you specifically deem reasonable. I know it sound crazy, but the world doesn't revolve around you in particular. VZ's "job" is to make money, and they do that using data communications services. This is because they're a profit driven organization in a capitalist driven society (the US). Their objective is to make as much money as they can for their shareholders. To do this they use some pretty basic economic principles, and they charge as much as the market will bear. While they cannot tailor individual product price points for individual people (deepest apologies) they try to ensure that their services are priced high enough that they make enough money on a per-transaction basis in order to bolster the organization's financial metrics, whilst not being too high that they don't get enough subscribers.
It's not greed. You're welcome.