No, it ends up being far cheaper than a Nexus 4. For many people, the point of a dumbphone like this is that you can save hundreds of dollars on data plans, or even more with prepaid.
Right now, I pay roughly $10 a month for my phone, and I'm reasonably happy with that (the reception is a bit weak, perhaps because the phone is so cheap, or perhaps because Tracfone is bad in my area).The problem is that my phone itself is terrible. The UI and the physical design are both atrocious.
I'd gladly drop $100 on a device that was pleasant to use. I've even contemplated shelling out a few hundred for a no-contract smartphone (I have wifi at work, wifi at home, etc...)