The phone wasn't always connected to wifi.
I got a Droid Incredible yesterday and went with the $15 a month data package. The sales rep told me I could use the wifi at my house and it wouldn't use up the 150 mb allotted with the $15 a month plan.
This morning I received a text from verizon telling me I had used my data for the month. I was connected to my wifi (at the house) last night and not using Verizon's network. Can you please explain how this might have happened?