Why is it that even though I have the router unplugged for several hours a day it still shows that I am using it?
Verizon can and does have a delay in data usage reports. Sometimes as much as 30 days if your roaming, Normally 24-72 hours delay is typical. To have a better Idea of your usage use a router that keeps tracks of usage..
The CradlePoint or Peplink Routers can help you with that. You can get the gear from 3gstore