This is a great article by CNET.com. Here are some of the basic reasons why smartphone companies do not allow you to just purchase voice only plans:
*They do not make money on calls anymore. That is why they are now offering unlimited voice calls.
*They make money from data
Here is the part that I found really interesting:
“If you’re willing to ditch Verizon and any of the other major carriers, you could try a new service from Republic Wireless, which costs only $19.99 a month for unlimited talk, text, and data. The carrier buys and resells capacity from Sprint Nextel’s network. But it also uses Wi-Fi networks. And because it uses Wi-Fi to carry the bulk of its data traffic, the company can offer such a low-cost service.
The company launched a beta version of its service about a year ago. But it was quickly so overwhelmed with users interested in the service that it had to shut down. It relaunched its beta service earlier this year. And starting next month, the service will be available to anyone.
The only catch is that, at least for now, it only supports one device, the Motorola Defy XT. That device is available for preorder now and costs $249 (plus $10 activation fee). Other smartphones will likely follow. And there’s even a chance that eventually, customers will be able to bring their own smartphones to the service. But for now, it’s just the Motorola Defy XT.”