I pay $50/month for my line and another $35 for my wife. I don't spend a lot of time on the phone and I don't text at all, but I have unlimited data. More importantly, I barely bother to look at my bill because I know what it's going to be in advance. The lack of admin more than makes up for any minor economic inefficiencies - I don't grudge the phone company making a profit off my relative underuse of the voice service.