The competition is charging higher rates too. This is the case in many states, no matter what carrier you choose for your IntraLATA calls. I used to work for AT&T and was familiar with the pricing of many carriers. In 90% of the states across the union it was more expensive than interstate calling. The only state that was cheaper was California. Some states, like yours, were as high as 3x the interstate price.
You could complain to the state commission if you feel strongly about it.
